F06 640d No sound (radio/door chimes/parking/etc.) - Harman Kardon amplifier probably toast!

[Kendo]

Hello gang, it's kind of something someone told me on this forum (the old version) in the past, 'good luck with the leaks' when I got my car 3 years back...

Being under extended warranty, never really bothered too much, but seems to have come back to bite me, and I'm now seeing it's a massive problem with multiple BMW models complaining of blown Harman Kardon amps.

Anyway, as title suggests, my brother borrowed car and came in this evening saying he could smell electrical burning and there's now no sound - I've precautionary checked all fuses, and they're fine so I'm presuming water has got in and blown the amp in boot (will check when there's better light).

Main questions are:

 

- Presuming It's likely water ingress... do we know common areas water gets in that I need to look at seals? (Presuming behind light clusters)

 

- Is there an aftermarket alternative/upgrade you can use in place of this Harmon Kardon (Logic 7) amp, or do I need like for like replacement?

 

Cheers in advance.