Steinberg Cubase Ai 5 Manual

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Synchronization
Using a KVM switchbox
If you want to set up a multi-computer network, or even a 
small network in a limited space, it is a good idea to invest 
in a KVM (Keyboard, Video, Mouse) switchbox. With one 
of these you can use the same keyboard, monitor, and 
mouse to control each computer in the system, and switch 
between computers very rapidly. KVM switchboxes are 
not too expensive, and very easy to set up and operate. If 
you decide not to go this route, the network will function 
just the same, but you may end up doing a lot of jumping 
from one machine to the other while setting up!
Making connections
Below, we assume that you are connecting two comput-
ers. Should you have more than two computers, it is still 
best to start with two and add the others one by one once 
the system is working – this makes troubleshooting easier 
if you run into problems. For two computers, you will need 
two digital audio cables, one in each direction:
1.Use the first digital audio cable to connect digital out-
put of computer 1 with the digital input of computer 2.
2.Use the other cable to connect the digital output of 
computer 2 with the digital input of computer 1.
If a card has more than one set of inputs and outputs, 
choose whichever one that suits you – for simplicity usu-
ally the first set is best.
Synchronization 
Before you proceed, you need to make sure that the clock 
signals on your ASIO cards are synchronized correctly. 
This is essential when cabling any kind of digital audio 
system, not just VST System Link.The Clock Mode or Sync Mode is set up in the ASIO con-
trol panel of the audio hardware. In Cubase AI, you pro-
ceed as follows:
1.Pull down the Devices menu and open the Device Set-
up dialog.
2.On the VST Audio System page, select your audio in-
terface from the “ASIO Driver” pop-up menu.
The name of the audio interface now appears as a subentry to the VST 
Audio System entry in the Devices list.
3.Select your audio interface in the Devices list to the left.
4.Click the Control Panel button.
The ASIO control panel appears.
5.Open the ASIO control panel on the other computer 
as well.
If you are using another VST System Link host application on that com-
puter, check its documentation for details on how to open the ASIO con-
trol panel.
6.Now, you need to make sure that one audio card is set 
to be the Clock Master, and all the other cards are set to 
listen for the clock signal coming from the Clock Master, 
i.e. they must be Clock Slaves.
The naming and procedure for this differs depending on the audio hard-
ware – consult its documentation if required. If you are using Steinberg 
Nuendo ASIO hardware, all cards default to the “AutoSync” setting – in 
this case you must set one of the cards (and only one) to “Master” in the 
Clock Mode section of the control panel.
Typically, the ASIO control panel for an audio card con-
tains some indication of whether the card receives a proper 
sync signal or not, and the sample rate of that signal.
This is a good indication that you have connected the cards and set up 
clock sync properly. Check your audio hardware’s documentation for de-
tails.
The only exception to this procedure is if you are using an 
external clock – which could be from a digital mixing desk 
or special Word Clock synchronizer for example. If so, you 
must leave all your ASIO cards in Clock Slave or AutoSync 
!All digital audio cables by definition always carry a 
clock signal as well as audio signals, so you do not 
have to use a special Word Clock input and output 
for this (although you may find that you get a slightly 
more stable audio system if you do, especially when 
using multiple computers).!It is very important that one and only one card is the 
clock master, otherwise the network cannot function 
correctly. Once you have set this up, all the other 
cards in the network will take their clock signal from 
this card automatically. 
						

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Synchronization
mode, and make sure that each of them is listening for the 
signal coming from the synchronizer, usually passed 
through your ADAT cables or Word Clock connectors in a 
daisy chain fashion.
VST System Link and latency
The general definition of latency is the amount of time it 
takes any system to respond to whatever messages are 
sent to it. For example, if your system’s latency is high and 
you play VST instruments in realtime, you will get a notice-
able delay between when you press a key and when you 
hear the sound of the VST instrument. Nowadays, most 
ASIO-compatible audio cards are capable of operating 
with very low latencies. Also, all VST applications are de-
signed to compensate for latency during playback, making 
the playback timing tight.
However, the latency time of a VST System Link network 
is the total latency of all the ASIO cards in the system 
added together. Therefore it is extra important to minimize 
the latency times for each computer in the network.
ÖThe latency does not affect the synchronization – it is 
always perfectly in time. But it can affect the time it takes 
to send and receive MIDI and audio signals, or make the 
system seem sluggish.
To adjust the latency of a system, you adjust the size of the 
buffers in the ASIO control panel – the lower the buffer 
size, the lower the latency. It is best to keep to fairly low la-
tencies (buffer sizes) if your system can handle it – about 
12 ms or less is usually a good idea.
Setting up your software
Now it is time to set up your programs. The procedures 
below describe how to set things up in Cubase AI. If you 
are using another program on the other computer, please 
refer to its documentation.
Setting the sample rate
The projects in both programs must be set to use the 
same sample rate. Select “Project Setup…” from the Pro-
ject menu and make sure the sample rate is the same in 
both systems.
Streaming digital audio between applications
1.Create input and output busses in both applications 
and route these to the digital inputs and outputs.
The number and configuration of the busses depends on your audio 
hardware and on your needs. If you have a system with eight digital i/o 
channels (such as an ADAT connection), you could create several stereo 
or mono busses, or any combination you need. The important thing is 
that you should have the same configuration in both applications – if you 
have four stereo output busses on computer 1, you want four stereo in-
put busses on computer 2, etc.
2.Set things up so that computer 1 plays back some 
audio.
You could for example import an audio file and play it back in Cycle mode.
3.In the Inspector or Mixer, make sure the playing audio 
channel is routed to one of the digital output busses you 
set up.
4.In computer 2, open the Mixer and locate the corre-
sponding digital input bus.
The audio being played back should now “appear” in the program run-
ning on computer 2. You should see the input bus level meters moving.
5.Reverse this procedure so that computer 2 plays back 
and computer 1 “listens”.
Now you have verified that the digital connection works as 
it should.
ÖFrom this point on in this chapter, we refer to the bus-
ses connected to the digital inputs and outputs as “VST 
System Link busses”.
Settings for the audio hardware
When you send VST System Link data between comput-
ers, it is important that the digital information is not 
changed in any way between the programs. Therefore, 
you should open the control panel (or additional applica-
tion) for your audio hardware and make sure that the fol-
lowing conditions are met:
If there are additional “format settings” for the digital 
ports that you use for VST System Link data, make sure 
these are turned off.
For example, if you are using an S/PDIF connection for VST System Link, 
make sure that “Professional format”, Emphasis and Dithering are turned 
off. 
						

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Synchronization
If your audio hardware has a mixer application allowing 
you to adjust the levels of digital inputs and outputs, make 
sure that this mixer is disabled or that the levels for the 
VST System Link channels are set to ± 0 dB.
Similarly, make sure no other forms of DSP (pan, ef-
fects, etc.) are applied to the VST System Link signal.
Notes for Hammerfall DSP users
If you are using RME Audio Hammerfall DSP audio hard-
ware, the Totalmix function allows for extremely complex 
signal routing and mixing in the audio hardware. This can 
in some situations lead to “signal loops” in which case the 
VST System Link will not work. If you want to make abso-
lutely sure this will not cause any problems, select the de-
fault or “plain” preset for the Totalmix function.
Activating VST System Link
Before you proceed, you need to make sure that VST Sys-
tem Link is set as Timecode Source in the Project Syn-
chronization Setup dialog and that the desired Sync 
options are activated, see “Sync Options” on page 240.
After setting up the inputs and outputs, you now need to 
define which input/output should carry the actual VST 
System Link information.
The System Link networking signal is carried on only one 
bit of one channel. This means that if you have an ADAT 
based system which normally carries eight channels of 
24-bit audio, once you activate VST System Link you will 
have seven channels of 24-bit audio and one channel of 
23-bit audio (the least significant bit of this last channel 
will be used for networking). In practice this makes no dis-
cernible difference to the audio quality, since you will still 
have around 138 dB headroom on this channel.
To set things up, open the VST System Link panel:
1.Open the Device Setup dialog on the Devices menu.
2.Select VST System Link in the Devices list to the left.3.Use the ASIO Input and ASIO Output pop-up menus 
to define which channel should be the networking channel 
(and thus become a 23-bit audio channel, in our example).Quite often you will be able to leave these pop-ups the way they are. 
4.Click the Active checkbox at the top of the panel.
5.Repeat the steps above for every computer on the 
network. 
As the computers are made active, you should see the 
small Sending and Receiving indicators flashing on each 
active computer, and the name of each computer should 
appear in the list at the bottom of the pane. Each computer 
is assigned a random number – do not worry about this, it is 
just so the network knows internally which one is which.
You can double-click on the name in bold (which is the 
name of the computer you are currently working on) and 
set it to whatever other name you wish.
This name will appear in the System Link window of every computer on 
the network.
ÖIf you do not see the name of each computer appear-
ing once you have made it active, you may have to check 
your settings. 
Go through the procedure above again and make sure that all ASIO 
cards are listening to the digital clock signals correctly, and that each 
computer has the correct inputs and outputs assigned to the System 
Link network. 
						

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Synchronization
Putting the network online
After each computer’s name you will see whether it is online 
or not. When a computer is online, it will receive transport 
and timecode signals, and its sequencer application can be 
started and stopped by remote control. If it is off-line, it can 
only be started from its own keyboard – it is effectively an 
independent machine, although it is still on the network.
ÖNote that any computer can control any and all of the 
others – VST System Link is a peer-to-peer network and 
there is no absolute “master” computer.
However, most users do like to think of one machine as the master (in a 
one person/two computer network, this would be the machine you actu-
ally sit behind most of the time). 
For now, let’s put all computers online:
1.Activate the Online checkbox in the VST System Link 
panel for all computers. 
2.Check that the system is working by pressing Play on 
one computer – all computers should start almost instantly 
and play perfectly in time, with sample-accurate precision.
The Offset setting allows you to adjust whether one ma-
chine will play back slightly ahead or behind the rest.
This is normally not needed, but occasionally with some hardware you 
may find that the lock is a few samples out. In that case you can adjust 
the lock with the Offset value. For now, leave it set to 0 – it will most likely 
be what you want.
The Transfer Bits setting allows you to specify whether 
you want to transfer 24 or 16 bits. This allows you to use 
older audio cards which do not support transfer of 24 bits.
VST System Link sends and understands all transport 
commands, so you can play, stop, fast forward, rewind, 
etc. the entire network from one computer without a prob-
lem – try it! If you jump to a locator point on one machine, 
all other machines will also instantly jump to that locator 
point. You can even scrub on one computer and have the 
video and audio on another computer actually scrub right 
along with you.
Using MIDI
As well as supplying transport and sync control, VST Sys-
tem Link also supplies up to 16 MIDI ports, each with 16 
channels. You set this up as follows:
1.Use the MIDI Inputs and Outputs value boxes to spec-
ify the number of MIDI ports you need.
The default value is 0 MIDI In and 0 MIDI Out ports.
2.Create a MIDI track in the Project window and open 
the Inspector (top section).
3.If you now pull down the Input or Output Routing pop-
up menu, you will find the specified System Link ports 
added to the list of MIDI Inputs and Outputs.
This allows you to route MIDI tracks to VST instruments 
running on another computer, as described in the applica-
tion examples (see “Using one computer for VST instru-
ments” on page 246).
The “Use Selected ASIO Ports for Data only” setting
If you are sending huge amounts of MIDI data at once, 
there is a small possibility that you might run out of band-
width on your VST System Link network. This will manifest 
itself by notes “choking” or timing becoming erratic.
If this happens, you can devote more bandwidth to MIDI 
by activating “Use Selected ASIO Ports for Data only” in 
the VST System Link Setup panel. When this is activated, 
the VST System Link information will be sent on the entire 
channel instead of just one bit, more than enough for all 
the MIDI you could ever hope to use. The downside is that 
!Make sure that all computers have their tempos set 
to the same value, otherwise your synchronization 
will be seriously skewed. 
						

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Synchronization
you can no longer use this ASIO channel for audio transfer 
(do not connect it to a speaker!), thus leaving you only 7 
channels of audio in our ADAT cable example. Depending 
on how you work this might be a reasonable compromise.
Hearing the network audio
If you are using an external mixing desk, hearing your audio 
really is not an issue – just plug the outputs of each com-
puter into the desired channels on the external mixing desk, 
press Play on one of the computers, and youre good to go.
However, many people prefer to mix internally inside the 
computer and just use a desk for monitoring (or maybe not 
use any external mixer at all). In this case you will need to 
select one computer to be your “main mix computer” and 
send the audio from your other computers into this.
In the following example, we assume you are using two 
computers, with computer 1 as your main mix computer 
and computer 2 running two additional stereo audio 
tracks, an FX channel track with a reverb plug-in and a 
VST instrument plug-in with stereo outputs.
1.First you want to set things up so that you can listen to 
the audio playback from computer 1.
In other words, you need an unused set of outputs, e.g. an analog stereo 
output, connected to your monitoring equipment.
2.Go to computer 2 and route each of the two audio 
tracks to a separate output bus.
These should be busses connected to the digital outputs – let’s call 
them Bus 1 and 2.
3.Route the FX channel track to another VST System Link 
bus (Bus 3).
4.Route the VST instrument channel to yet another bus 
(Bus 4).
5.Go back to computer 1 and check the corresponding 
four VST System Link input busses.
If you start playback on computer 2, the audio should “appear” on the input 
busses on computer 1. However, to mix these audio sources you need ac-
tual mixer channels.
6.Add four new stereo audio tracks on computer 1 and 
route these to the output bus you use for listening, e.g. to 
the analog stereo outputs.
7.For each of the audio tracks, select one of the four in-
put busses.
Now, each computer 2 bus is routed to a separate audio channel on 
computer 1.
8.Activate monitoring for the four tracks.
If you now start playback, the audio from computer 2 will 
be sent “live” to the new tracks on computer 1, allowing 
you to hear them together with any tracks you play back 
on computer 1.
For more information about Monitoring, see “About moni-
toring” on page 13.
Adding more tracks
What if you have more audio tracks than you have VST 
System Link busses (physical outputs)? Then you just use 
the computer 2 mixer as a submixer: Route several audio 
channels to the same output bus and adjust the output 
bus level if needed.
Note also that if your audio cards have multiple sets of in-
put and output connections you can link up multiple ADAT 
cables and send audio via any of the busses on any of the 
cables.
Internal mixing and latency
One problem with mixing inside the computer is the latency 
issue we mentioned earlier. The VST engine always com-
pensates for record latencies, but if you are monitoring 
through computer 1 you will hear a processing delay while 
you listen to signals coming from your other computers (not 
on your recording!). If your audio card in computer 1 sup-
ports ASIO Direct Monitoring you should definitely turn this 
on – you can find the setting in the VST Audio System De-
vice Setup panel (see “ASIO Direct Monitoring” on page 
53). Most modern ASIO cards support this function. If 
yours does not you may want to change the Offset value in 
the VST System Link Setup panel to compensate for any la-
tency issues.
Setting up a larger network
This is not much more difficult than a two computer net-
work. The main thing to remember is that VST System Link 
is a daisy chain system. In other words, the output of com-
puter 1 goes to the input of computer 2, the output of 
computer 2 goes to the input of computer 3, and so on 
around the chain. The output of the last computer in the 
chain must always go back into the input of computer 1, to 
complete the ring. 
						

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Synchronization
Once you have done this, the transmission of all the trans-
port, sync, and MIDI information to the whole network is 
handled pretty much automatically. However, where you 
may run into confusion in a large network is in the trans-
mission of audio signals back to a central mix computer.
If you have lots of hardware inputs and outputs on your 
ASIO cards you do not have to send audio via the chain at 
all, but can transmit it directly to the master mix computer 
via one or more of its other hardware Inputs. For example, if 
you have a Nuendo Digiset interface or 9652 card on com-
puter 1 you could use ADAT cable 1 for networking, ADAT 
cable 2 as a direct audio input from computer 2, and ADAT 
cable 3 as a direct audio input from computer 3.
You can also transmit audio via the ring system if you do 
not have enough hardware I/Os for direct audio transmis-
sion. For example, in a four computer scenario you could 
send audio from computer 2 into a channel in the mixer in 
computer 3, and from there to a channel in the mixer in 
computer 4, and from there back to the master mixer in 
computer 1. This can certainly be tricky to set up, so gen-
erally it is recommended that if you want to set up a com-
plex network, you should make sure to use ASIO cards 
with at least three separate digital I/Os. 
Application examples
Using one computer for VST instruments
In this example, one computer will be used as main record 
and playback machine, and another computer as a virtual 
synth rack.
1.Record a MIDI track into computer 1.
2.Once you have finished recording, route the MIDI out-
put of that track to System Link MIDI port 1.
3.Now go to computer 2, open up the VST Instrument 
rack and assign an instrument to the first slot in the rack.
4.Route the VST Instrument channel to the desired out-
put bus.
If you are using computer 1 as your main mixing computer, this would be 
one of the VST System Link output busses, connected to computer 1.
5.Create a new MIDI track in the Project window of 
computer 2, and assign the MIDI output of the track to the 
VST Instrument you created. 6.Assign the MIDI input of the track to be VST System 
Link port 1.
Now, the MIDI track on computer 1 is routed to the MIDI track on com-
puter 2, which in turn is routed to the VST Instrument.
7.Now activate monitoring for the MIDI track on com-
puter 2, so that it will listen and respond to any MIDI com-
mands coming in.
In Cubase AI, you would click the Monitor button in the Track list or In-
spector.
8.Start Playback on computer 1.
It will now send the MIDI information on the track to the VST Instrument 
loaded on computer 2.
Even with a slow computer you should be able to stack a 
whole bunch of extra VST Instruments this way, expanding 
your sound palette considerably. Do not forget that VST 
System Link MIDI is also sample-accurate, and thus has 
much tighter timing than any hardware MIDI interface ever 
invented!
Creating a virtual effect rack
The effect sends for an audio channel in Cubase AI can 
either be routed to an FX channel track or to any activated 
Group or output bus. This allows you to use a separate 
computer as a “virtual effect rack”, by setting things up in 
the following way:
1.Go to computer 2 (the machine you will use as effect 
rack) and add a new stereo audio track.
You cannot use an FX channel track in this case, since the track must 
have an audio input.
2.Add the desired effect as an insert effect for the track.
Let’s say you add a high-quality reverb plug-in.
3.In the Inspector, select one of the VST System Link 
busses as input for the audio track.
You want to use a separate System Link bus, which will only be used for 
this purpose.
4.Route the channel to the desired output bus.
If you are using computer 1 as your main mixing computer, this would be 
one of the VST System Link output busses, connected to computer 1.
5.Activate monitoring for the track.
6.Now, go back to computer 1 and select a track to 
which you want to add some reverb.
7.Bring up the effect sends for the track in the Inspector. 
						

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Synchronization
8.Open the Send Routing pop-up menu for one of the 
sends, and select the VST System Link bus assigned to 
the reverb in step 3.
9.Use the Send slider to adjust the amount of effect as 
usual.
The signal will be sent to the track on computer 2 and pro-
cessed through its insert effect, without using any proces-
sor power on computer 1.
You can repeat the steps above to add more effects to the 
“virtual effect rack”. The number of effects available this way 
is only limited by the number of ports used in the VST Sys-
tem Link connection (and of course by the performance of 
computer 2, but given that it will not have to handle any re-
cording or playback, you should be able to use quite a lot of 
effects).
Getting extra audio tracks
All computers on a VST System Link network are locked 
with sample-accuracy. Therefore, if you find that the hard 
drive on one computer is not fast enough to run as many 
audio tracks as you need, you can record new tracks on 
one of the other computers instead. This would create a 
“virtual RAID system”, with several disks all operating to-
gether. All tracks will remain locked together just as tightly 
as if they were all running on the same machine. This 
means that you effectively have an unlimited track count! 
Need another 100 tracks? Just add another computer. 
						

							23
Video 
						

							249
Video
Background
Cubase AI plays back video films in a number of formats. 
Under Windows, video playback can be done using one 
of three playback engines: Video for Windows, DirectS-
how or QuickTime 7.1. This ensures compatibility with as 
wide a range of video files as possible. The following file 
formats are supported: AVI, QuickTime and MPEG.
Under Mac OS X, QuickTime is always used as playback 
engine. QuickTime supports the following video file for-
mats: AVI, MPEG, QuickTime and DV.
There are two ways to play back video:
Without any special hardware.
See “Playing back video without any hardware” on page 250.
Using video hardware that, for example, connects to an 
external monitor.
See “Playing back video file using video hardware” on page 251.
Before you start
When working on a project involving a video file, there are 
several points to bear in mind:
Have you selected the right playback engine? 
(Windows only)
The playback engine is used not only for playback of the 
video file, but also to provide file information in the Pool and 
in the Import Video dialog. Therefore, to make sure that you 
have chosen the right playback engine for a particular type 
of video file, check the file information displayed in the Im-
port Video dialog or the Pool prior to trying to import or 
playing back the file.
When this information reads “0x0 pixel”, “0.000 s” and “0 
Frames”, the video file is either corrupt, or the format is not 
supported by the codecs available to the selected video 
playback engine. You will either have to change the video 
playback engine, or install the required codec.
About the QuickTime video playback engine
In Cubase AI for Windows, you select a playback engine 
in the Device Setup–Video Player page:
Generally, you can expect most Windows hardware to 
work with DirectShow.
On a Windows system, the DirectShow and Video for Windows players 
are provided by the operating system, so you do not have to install any 
additional software.
Under Windows, QuickTime 7.1 must be installed on 
your computer for QuickTime playback to be available.
There is a freeware version (a QuickTime installer is included on the Cu-
base AI DVD if required, or you can download it from www.quicktime.com) 
and a “pro” version, which offers additional video cutting options. The en-
gine is the same in both versions, so for mere playback in Cubase AI there 
is no need to purchase the “pro” version.
!Trying to import or play back a file not supported by 
the selected video playback engine leads to unpre-
dictable results – if no information on the number of 
frames, the length and the pixel resolution is available 
in the Import Video dialog or the Pool, you cannot im-
port/play this file properly with this particular video 
playback engine.
!You can change the video playback engine in the 
Device Setup dialog. After having done so, make 
sure to remove any previously imported video file 
from the Pool first, and re-import it. 
						

							250
Video
Under Mac OS X, only the QuickTime playback engine 
is available, supporting the formats AVI, MPEG, Quick-
Time and DV. If your system has a FireWire port, there is 
also a FireWire option – see below.
Video quality in QuickTime
When you are using QuickTime as your video playback 
engine, you can select “High Quality” from the Video win-
dow context-menu, or “Use high-quality video settings 
when available” in the Device Setup dialog, Video Player 
page, in the Video Properties section for QuickTime.
When your QuickTime video was recorded with the cor-
responding quality settings, selecting the “Use high-qual-
ity video settings when available” or the “High Quality” 
option will make the video display sharper and smoother. 
Note that this will also lead to increased processor load.
Video playback preferences
In the Preferences (Event Display–Video page), there are 
two options for video playback:
Show Video Thumbnails.
When this is activated, thumbnail frames of the video contents are shown 
in the track.
Video Cache Size.
This determines how much memory is available for video thumbnails. If you 
have long video clips and/or work with a large zoom factor (so that a lot of 
frames are shown in the thumbnails), you may have to raise this value.
Playing back a video file
Video files are displayed as events/clips on the video 
track, with thumbnails representing the frames in the film 
(if the option Show Video Thumbnails is activated in the 
Preferences, see above).
A video event on a video track
In the Track list and Inspector, you will find the following 
controls for video tracks:
To view the video on the computer screen (as opposed to 
on an external monitor, see below), proceed as follows:
If you’re running Mac OS X, open the Device Setup dia-
log from the Devices menu, click “Video Player” in the list 
and make sure “Onscreen Window” is selected in the 
Video Output section of the dialog. 
Under Windows, either pull down the Devices menu 
and select Video, or use a key command – by default [F8], 
or double-click the video clip.
A video window appears. In Stop mode, this displays the video frame at 
the project cursor position.
The video will be played back together with any other 
events in the Project window as usual.
Playing back video without any hardware
For the DirectShow video player, open the Device Setup 
dialog from the Devices menu, click Video Player in the De-
vices list and use the buttons in the Video Properties sec-
tion to select a size or right-click in the video window to 
switch to full screen. Right-click again to exit full screen.
For the QuickTime player (Windows and Mac), you can 
drag the borders, just like resizing other windows. You can 
also right-click in the video window to open the Video win-
dow context menu and select one of the Size options. 
There is also a Full Screen Mode available in the menu. 
Right-click again or press the [Esc] key on your computer 
keyboard to exit full screen mode.
ÖPlaying back video on your computer screen puts a limit 
on the size of the video window as well as the image quality.
!QuickTime as a video playback engine is available 
only if you have QuickTime 7.1 (or higher) installed 
on your computer. If you do not have QuickTime, or if 
a version lower than 7.1 is installed, this option will 
not be available in Cubase AI.
Button Description
Mute Video When this is activated, video playback will be stopped, 
but playback of any other events in the project will con-
tinue (to decrease the processor load). You may have to 
use the Track Controls Settings dialog to make this but-
ton visible in the Track list.