Hi David,
If you have your timeline expanded to the fullest, you should be able to count 30 (NTSC) "Tick marks" not sure of the official name...and 25 "tick marks (PAL) to get ONE SECOND on the timeline.
So you can't move your audio track only a 1/2 tick mark, which would be 1/2 a frame. You can only move things on whole frames. PD snaps-to the next available spot that you can move your clips, which is 1 frame.
Does that make sense? You should ba able to sync your audio track adequately with that level of precision. Is this not the case?
Regards,
Kevin
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