Occasionally when i start my car i hear a buzzing noise from the rear drivers side speaker. The odd thing is when you turn the car off and the radio is running off the battery, the buzzing goes away. I checked the connections to the radio and they're all secure and taped up. (aftermarket HU) Any ideas of what the buzzing could be coming from?

Do you have the premium/bose system? Also is it only when you turn the car on and/or when you turn the radio off? If yes to those the it is a bad amp I have the same problem and can;t seem to find my type of amp. You need to disconect that speaker or it will get very hot and give off a burning smell.My guess is that if you eave it connected it will start a fire.

yeah I have the bose system. The buzzing only happens when the engine is on. When the engine is off and the radio is on, the buzzing goes away.

Hmmm well I'm not sure then. Sorry man.

Well, I have a buzzing in one of my speakers, and when I put my car in the shop (for something unrelated) and they unplugged the battery, for some reason, the buzzing went a way for a while. My friend says it's a blown speaker (and it came that way, I didn't do it. lol)