Sound not working when uploaded to youtube

[benkramer]

Whenever i upload my video to you tube the sound disapears. Whats going on?

[RobiePAX]

The sound entirely disappears that you don't hear anything at all? Or only a portion of some sounds disappear such as your commentary but the rest can still be heard? Also can you hear the sound when you playback the video which you used to upload to YouTube?