File not playing in VLC

The issue is that the audio is encoded with a codec that isn't supported by VLC. If it's not supported by VLC, then odds are there are no free programs that do. You're basically going to be stuck using QuickTime for those specific files so you have my sympathies.

When I open it with Quick Time, it says additional plugins are required to play this type of file. It takes me to a download page. What plugin should I get for the audio to be playable?

if you ready to give up .mov formats than try "handbrake" to convert your files into mp4 or mkv..
or .mov is your's priority , then download "format factory" and choose all to MOV( yes .mov to .mov, but if your older files may have some codec issues, this will fix it)
just try with 1 file to check, if converted new file works fine vlc, then you may convert rest of your files
both handbrake and format factory are freeware, so just give a try

I don't need the files to be .mov. They can be anything popular (avi wmv mp4) as long as they play the audio.

then download handbrake or format factory , convert them to avi or mp4..

but "just try with 1 file to check, if converted new file works fine with vlc, then you may convert rest of your files "

When I play the video back on the camera I recorded it on, I can hear the audio, but when I transfer it and play it on the computer (Mac or Windows) with Quicktime or VLC, I don't hear anything.

what camera you got,, brand and model number...
generally vlc has it's own codecs , so no choice for any codec pack for it,, better get klite codec pack & try to play the video using media player classic or any other player ,

The camera I'm using is a Canon. Not sure about the model number - I will check that and tell you. I will try Media Player Classic and see if that works.

Could I request for this topic to be closed please by one of the moderators? Thx.

I don't need it open any longer