Bought a 1999 Lexus LX470 as my first car around 4 years ago. The previous owner put in an aftermarket sound system (double din head unit, amplifier, replaced all speakers and the subwoofer in the back), which works fine most of the time, but the subwoofer sometimes makes a loud static/crackling noise that sounds most similar to a dragon or flamethrower. Spoke about it with some friends and they seem to think it could be a bad ground? It only comes out of the subwoofer, not any other speakers.

Had to do a few other projects that involved removing some of the interior trim so I went ahead and pulled the subwoofer. The first thing I noticed was the missing chunk of plastic in the enclosure, some pieces of that plastic were lying in the bottom of the enclosure and I pulled them out. There’s also a pad of felt sitting there that doesn’t seem to be attached to anything.

Any suggestions on how to fix the crackling subwoofer noise? Would a good car audio shop be able to diagnose if the sub is broken?

Another issue I’ve had is that the audio system seems to briefly disconnect and then turn off entirely when it’s running for hours during hot ambient temperatures. I took a 5k mile/10 day trip during the summer and it would turn off after around 4 hours each day, the amplifier was incredibly hot and I couldn’t even unplug any of the cables coming in/out of it without wearing gloves. It’s located under the front passenger seat.

Any advice greatly appreciated!

Subwoofer intermittently sounds like a dragon breathing fire