Is the Media Sub Type for the music videos set to "Music Video". If not, select the tag option in the action window (i.e. the lower left corner of screen). Scroll down to Media Sub Type and select accordingly.
Does that fix it?
If not, go to the Music Video view, right click Customize View and look at the Set rules for file display dialog. In here you can limit what files are displayed. If you have done the above, you want to make a rule that all files should have Media Sub Type = Music Video.
Does that help?
Craig
