I've got a buzzing coming from the front driver door speaker when the engine is on. When the engine isn't running it isn't there, and it doesn't change pitch or volume based on revs. I'm guessing I need to replace the amp? Seems like others have replaced the amp and that fixed it. This same speaker also sounds like it's partially blown - it isn't as loud or as trebly as the other front door speaker.

Any good source for OEM amps for a '04 TL or a drop-in aftermarket replacement?

 

I would replace speaker first.
Besides auto sound shops ...
http://www.uneedapart.com

 

If it isn't there with the engine off, it's not the speaker.

Seems like there are more and more of these threads popping up. I believe the problem is the factory amp but I'm not sure if anyone has actually replaced it yet. I have one, I was holding it for another guy but if he doesn't get back to me, you can have mine.

I guess the '04 and '06 are the same part# so I'm assuming the changes are done in the HU.

 

If your stock amp is available I'll take it. PM me if you're interested.