Problems with uploading

This week, our music video was uploaded to youtube, however it seemed as if it was an incomplete video as the sound on the video clip was turned up in some places and a few random white clips were flashing halfway through. After going to the teacher to ask whether they had uploaded the correct video, we watched the video back on their computer and these problems were not visible and the white flashes occured in a different place instead. As our teacher had already seen the completed video where these problems do not exist we have just left it as we think it's a problem with the file rather than what we have actually created.