Download File has No Audio
The YouTube Downloader shows many different available file formats, but not all of these have audio. The program reads the metadata of these files
and displays only those with 2 channels (audio and video) of data. However, we cannot detect inside of the codec to determine if one of the channels
is empty, so it is possible you have downloaded a file that has a video channel with data and an audio channel that is empty.
You can check this by opening the video in Windows Media Player or iTunes/QuickTime. Another thing you can do is choose the file labeled "Best".
This file should have both audio and video data.
If you still have problems after checking the above, please complete a Help Desk Ticket.