Discovery 2 - front right speakers no sound

I have an aftermarket stereo fitted in my 2003 D2 - used to work perfectly. Now the front right speakers don't have sound - if you stick your ear by them you can just about hear something. Rear right all fine - and rest of car all fine. Is there a fuse to check? No-one has tampered with the wiring at the back of the stereo... Many thanks for any ideas!

So - just blasted at top volume and the A pillar and small speaker at the top of the door now work - but the bass speaker does not. Assume this needs replacing?

Hi, it could just be badly corroded connections to the speaker but you'll have to take the door card off to check.

Looked through previous posts so checked the wiring in the rubber door conduit - bingo, two broken wires. All fixed now!