I bought a BMW 745 Li, the sound system works, but the speakers keep popping when you turn the bass up. It really sounds like the subwoofers or something is slightly disconnected. Where are the subwoofers anyway, it sounds like the popping sound is coming from under the passenger seat. How can I check this?
Hi, this is a very common problem on these cars. It is simply an amplifier that has failed. There is a subwoofer under each front seat. When thd amp fails you will get no bass or it will pop exactly as you described. The only thing you can do is replace the amp. Id recommend finding a known good and tested used one. The new ones are very expensive from the dealer.The amp is the long aluminum rectangular box behind the left trunk trim panel. You'll need to know if you have logic 7 or not when ordering a new one. It will say logic 7 on the audio settings screen and also on the amp. Check eBay, they should have some.