Any resolution to this? I've had the problem on and off and it's currently hauting a pretty long animation sequence. I thought it was that I started in 29.97 and switched to 23.976. So I moved to 24 and still no joy. Other sequences in the file are fine.
I think I got it. In the timeline menu at the top right (three stacked horizontal bars) there is a move and trim option. If you set the playhead where you want, click the animation and, then click move start to playhead it will fix the problem.