edit audio in compositing mode Assume you are in compositor mode and you have a video as an input source. The audio isn't immediately played along the video. Usually I re-import the video in VSE mode again and strip away the video information.

1st question: is this the intended work flow to add audio?

A problem that comes from this is, that once you have a scenario where audio and video are out-of-sync it is nearly impossible to sync them. This is because switching between compositing and VSE mode doesn't allow to adjust the audio easily.

2nd question: how do you guys sync your audio?
You don't.

You worry about frame accuracy during editorial, lock your picture (no further editing), and then commence post production work.

At the point you have completed your edit, your motion picture is not being adjusted any further, and the frames are locked.

When you are finished with your post work, you simply take the output frames, per shot, and re-slug them back into where your original editorial frames were.