2thousand2

Sorry if this should have went in stereo and electronics, wasn't sure since this stereo setup is only in the Grand Prix models.

My girlfriend just bought a 2005 Pontiac Grand Prix GTP (most likely has the same system as the GXP crowd) and is having stereo speaker noises.

When you hit a bump a crackling popping sound comes from the passenger rear speaker usually and sometimes the driver rear or the front passenger door speaker. You also hear engine noise in a whining pitch through the speaker when it is happening. Once you hit another bump, restart the car, or unplug the speaker doing it or the amp in the truck all together...it will go away. It will do it on and off throughout a drive to the point where it will drive you insane.

If you turn off the radio you still hear it until you hit a bump again or the above mentioned things happen.

Anyone had to bring theirs in for warranty work and had this problem fixed? Something like it?

Please help, this is a great/badass car otherwise we just don't wanna change out each expensive part to possibly fix the problem.

Thanks,
Nick

06 SS

look for loose grounds.

nmp0098

I think there was a TSB for the Monsoon Amps relating to blown center channels, so if all of your connectors are snug it may be a bad amp. The dealer may be able to let you know more. I'm intermittently getting the same thing out of the rear passenger mid range channel, but I voided my warranty pretty thoroughly. It may even be a bad connection on that speaker. A used Monsoon Amp is like $20 at the junkyard if the amp is the problem and it's not covered by warranty for whatever reason.

2thousand2

Everyone always says this...but which ones and where are they located?

Thanks, I'll check that out. If you hit the dash while its doing it, it will stop also...maybe its inside the head unit?

Sittingmongoose

iTrader: (1)

I had this exact same problem. I have the dealership replace the amp and it fixed the issue. But make sure that the speakers arent blown cause mine were from the noise. They will replace them under warrenty if you still have one.

nmp0098

It could be the head unit, but hitting the dash would effect your center channel, not the amp. The amp is in the trunk, mounted to the rear deck lid. It sounds like you have a blown center channel, because noise from a blown speaker can be intermittent. Mine blew a few days after I got the car, but I just replaced it with an aftermarket speaker. The center channel is just a crappy paper cone speaker that would cost $2 at most electronics stores.

If you only upgrade 1 speaker in the car, I'd recommend the center channel because it makes a big difference in what you hear (at least for the driver and front passenger) and because aftermarket 3 1/2" speakers are cheap.

I'm pretty sure that I am screwed on the amp recall because I soldered in some RCA's for the sub and completely redid the rear speakers, but I think I have the same issue.

DP 08 GXP

iTrader: (3)

i plan on getting a new amp, 6x9's, and a component package for the doors. someone told me that i will lose the center speaker when i replace the amp. does anyone know if this is true?

nmp0098

Yes, you will lose the center channel. The head unit outputs 4 channels (LF, RF, LR, RR), and the Monsoon amp powers 9 speakers. It creates a center channel and a subwoofer channel. The rear 6x9s are counted as two speakers. The 2" channel of the 6x9 is called a mid range and there is a left and right. The 6x9 parts of the 6x9 speakers are wired in parallel for a 2 ohm load, and amped off a single channel. They are considered the subwoofers. In the front doors, the mid-ranges and tweeters are amped seperately too.

Warning: most of the Monsoon head units have a 6V offset, and that messes with some aftermarket amps. My MTX was fine, but I have heard of people getting ground offset issues.

DP 08 GXP

iTrader: (3)

i have a pioneer nav/dvd unit so i should be fine there....thanks for the reply

2thousand2

Ok I will try a a front center channel speaker first, a rear amp, then rear speakers, then a head unit till it gets cured. The car is no longer under warranty, we just bought it but it did not come with any warranty as it has been more than 30 days and the car has 80k miles. If anyone has any other suggestions I would appreciate them!

bdyman

i had the same problem and replacing the monsoon amp fixed the problem

98GTcoupe

Ditto......