There are times when Pro Tools does not playback your audio, or the playback seems delayed. I can think of a number of reasons that could be a contributing factor. In this article we will look at the underlying causes for Pro Tools playback issues and the possible solutions to these problems.
Buffer size is what determines the time it takes for your computer to process sound from your audio interface. A smaller buffer size allows your computer to process sound faster but with increased demand on your computer’s processing power. Typically, you want a lower buffer size (128 or 256 samples) when recording and a higher buffer size (512 or 1024) when listening to something in Pro Tools.
The same concept applies to other Digital Audio Workstations. Using the wrong buffer size will lead to a higher load on your computer’s processor and will result in latency. In some extreme cases it can cause playback to fail entirely. For example, when you are running multiple instances of resource-heavy plug-ins. Other times Pro Tools may give you an error message stating that “Pro Tools Ran Out of CPU Power”
To change the buffer size in Pro Tools, go to Setup and select Playback Engine.
In the Playback Engine dialog box, the buffer size can be selected in the H/W Buffer Size drop down menu.
If you are attempting to play something but there was no playback and the Sample size was already set to 1024 samples, then consider setting it to 512 Samples instead.
Transport Online is Selected
Transport Online enables Pro Tools to receive Timecode from other devices. If Transport Online is selected, it might cause Pro Tools not to play since it would be waiting to receive Timecode from an external source such as another sequencer.
You will be able to tell that this feature is active if the Transport Online icon is blinking blue there will also be a message near the bottom left of the Edit Window that indicates that Pro Tools is Waiting for Sync. To turn off this feature, simply click the Transport Online icon located in the Transport Controls
Alternatively, Transport Online can be deactivated from the Options menu or by using the keyboard shortcut Ctrl + J on Windows or Command + J on Mac
Count Off May Be Active
Count off is a feature in Pro Tools that delays the start of playback by a number of bars. For example, if the count off is set to one bar, there will be a bar of metronome tick before playback starts. If there is no click track in your session while count off is enabled, then there will be a bar of silence which can lead some users to believe there is a playback issue occurring.
When count off is enabled, the play button will flash on and off for the period of the count off before playback starts. Count off can be deactivated from the Transport Controls section. If you cannot see the count off option, click the small downward pointing arrow on the top-right of the edit window to expand what options can be seen in this section by selecting “MIDI Controls”
Count Off can also be activated or deactivated using the click/count off options dialog that can be accessed from the Setup drop-down menu. Further options relating to click and count off can also be found here.
Loop Playback May Be Active
Loop Playback is a feature in Pro Tools that allows you to play any selected region in a session on repeat as long as the selected region is longer that 1.5 seconds. If this feature is active and a selection has been made, it may be interfering with “normal” playback.
If Loop Playback is active and a selection shorter than 1.5 seconds has been made, hitting the play button or Spacebar will make Pro Tools only play the small selection then stop playback. You can tell when this Playback mode is active when the Play button, instead of being a green triangle, is instead a triangle with a looped arrow as shown below.
To turn off Loop Playback, right-click the play button and deselect “loop”. Another way to do this is to deselect “Loop Playback” in the Options menu.
The simplest way is using the Keyboard shortcuts Ctrl + Shift + L on Windows and Command + Shift + L on Mac.
From this article we see that there are various issues that affect playback in Pro Tools. Some of these come from certain features being turned on or left on accidentally. Others from a strain on your computer’s resources. With a bit of know-how on Pro Tools inner workings, and following a few simple steps, you will be able to resolve these issues and get back to work in no time.