- Live Versions: 1 - 9
- Operating System: ALL
A phase cancellation test will fail when routing returns back to an audio track.
The reason for this is the way how Live handles the audio signal flow and calculates audio signals.
In a nutshell:
Live 'looks' at all tracks, collects the data of the current audio sample which needs to 'leave' the computer next and sends it to your audio driver. This is called one calculation cycle. Once this has been done, it starts the next calculation cycle for the next sample and so on. If an audio signal from a return track is routed back into an ordinary audio track, it might be late, because the previous calculation cycle (which contained the data of your audio and MIDI tracks) has already been finished and has literally left the computer. This makes it impossible to get complete phase cancellation in such a scenario.
Generally, we recommend to check if there are any feedback loops in your set (Routing example: track sends → return track → track input) to avoid this problem.