iPod iPod 3G no sound?

[0098386]

My girlfriends 3G iPod isn't working as it should.

Firstly it won't sync over FireWire anymore on XP or OSX, but does sync with USB. It also charges over FireWire still. Diagnostics Mode tells me the FWid thing is fine.
Secondly, and just recently, it won't output any sound. It doesn't even pause music when headphones are ejected.

We put a new battery in the thing a good few months ago and was working after the "operation".

Any ideas? Is it common for a 3G to do this kind of thing?

 

[0098386]

Well! It turns out the internal headphone cable thing had become disconnected. That's back in. But it still won't sync over FireWire. It's connected to my Mac now and it just charges.