Playhead stops moving in timeline

After using FCP a while, and it seems, after exporting something to compressor, the playhead stays put in the timeline. The video plays - although sometimes stutters - but the playhead doesn't move. If I restart FCP, all is fine.

Any thoughts?

Sorry- No answer here- but a confirmation of symptom. My playhead does the same thing, seemingly after the project has been sitting idle for a bit. I hit play- it does- but playhead doesnt advance to new location till I stop playback..

Did you ever get an answer?

Thanks

paul