I have footage from camera 1 on track one and footage from camera 2 on track two and a seperate audio track recorded on a zoom located on the audio track. Because of problems with the zoom audio (DJ mike cut in and out) it sounds better when the audio from track one and the Zoom are combined.
I did the Sync by Audio option for these two items and placed them where I wanted in the timeline. Problem is, when I add a transtion between video segments it moves the audio and video for track one and un-syncs the audio. If I try the Sync by Audio options on the clips again, they both jump together to new tracks on the time line and when I move them back to the original track one location, the transitions is gone...as soon as I add the translation again...it moves the track and unlinks the audio all over again???
This problem would also come up when recording audio straight from a sound board to get the mics and music and combining it with the audio from the camera to get the live crowd sounds, clapping etc. at a reception. You can Sync by Audio but as soon as a transition is added it breaks the sync...