I want to check if other users have this problem. I found something like a bug whenever I upload a .mov file compressed from a FCP X project. The video plays back on YouTube but the audio sync is off by exactly 1.79 frames. The reason why I know this is if I import the ProRes 422 / ProRes 422 HQ file back into FCP X, detach audio, trim the beginning by 1.79 frames, and then move it back by that amount and then re export, re compress, and re upload to YouTube then the audio is perfectly in sync. When I import a finished video in ProRes 422 / ProRes 422 HQ format back into FCP X and detach audio, when I trim the beginning of the audio finely, it will go all the way up to 1.79 frames and then jump to 2.00. I don't know why it does this, only that it WILL mess up the audio sync if I upload directly to YouTube before re importing , trimming to 1.79, moving it back, and then uploading THAT video. Can anyone else confirm? I'm using FCP X 10.0.4 , 10.6.8, and I have some plugins on FCP X such as FX Factory, DV Shade, and some 3rd party particle generators. Before about February of this year this wasn't an issue at all.