Movie playback lags SMPTE counter, self-corrects when advance by frame

Question

Recently playback of my QT movies has begun to lag the SMPTE counter by about 15 frames. At any given point when playback is stopped, the timecode burn in the QT reads appx 15 frame behind the SMPTE counter. Curiously, when I advance by 1 frame (using key command), or advance by measure, or jump to marker, pickup clock of region, etc., the video instantly snaps forward to the exact SMTPE code in the counter. Lag only occurs during playback. This actually makes the problem worse, because I can't merely change the start time of the movie to compensate.
I've been using Logic for years without any sync problems. The problem is not file specific — the same lag occurs in Logic sessions I did just weeks ago with no sync problem.
Any thoughts or insights much appreciated.

Answer 1

Solved it – hope this helps someone else.
By moving (and saving elsewhere) my Logic preferences, I narrowed it down a preferences problem. Turned out to be my setting for plugin delay compensation – not an early suspect, given that it is for AUDIO. I had it set to "All", in order to eliminate the several frame shift rendered to my bounces when using the AdaptiveLimiter. After setting it to "audio tracks and instruments", the video lag ceased.
It will difficult to remember to change that setting every time I bounce a final mix, but at least the problem is solved.