So last few days one of the speakers has randomly started crackling/ popping ig theres a decent amount of bass put throught it. Using the front/rear & left/right faders Ive narrowed it down the main speaker in front passenger door. It has Audi concert headunit with B&O surround. Does it when playing CD (best song ive found to get it to do it was Double Barrel by Dave & Ansel Collins of all things!) But also does it a little when on radio. Doing some googling it appears its a common thing in A3's a few years back... What, if any is the fix for this? Audi can supply a "speaker" of some description for £57+vat but couldnt at that time garantee it was the B&O part of OE pov spec speaker.