Do you hear any sounds at all? For example, if you make a video, can you play it back and you can hear it?

If you play something other than youtube (like the online radio?) can you hear this?

Also, (and I know this might sound stupid), but youtube has it's own volume level.

Look under a video and you'll see a little speaker kind of thing. If it says the word MUTE, that means that it should be working. If you don't see the word mute, then IT'S ON MUTE.

Try and slide the lever over to the right, which will bring up the volume

Let me know what happens. This happened to me once. I could hear everything on other stuff but not on youtube. That's how I found about about the volume level thing on the bottom of any video on youtube.


Update:

I made a video showing how this is done. You probably already know this but just in case you don't here you go!!

http://www.youtube.com/watch?v=kjtWeEK49Ug

Melody
Melody