HELP!! I have an 07 coupe with the Lt1 package. Basic stock radio, no HUD, no bose or nav. I purchased a Kenwood DNX 8120 with blue tooth, nav, and XM from Crutchfield to replace my stock radio. I had BestBuy (my first mistake) install the unit and have had multiple problems with sound quality. When I start the car there is a static sizzle that lasts until the word "chevrolet" pops up on the driver info display. The front speakers continue to have static that last for several miniutes before fading away. When i turn the unit up about half way, the front speakers make popping/cracking sounds. I have taken it to the dealer and they say the speakers are fine and BestBuy has tried twice to fix the problem with no success. Bottom line is I have the worst sound quality I have ever heard after spending about $2000.00 once all was said and done.

Any feedback would be appreciated

 

First thing to check is whether Best Buy used an an adaptor or not. There is an adaptor used to connect aftermarket stereos to the stock GM wiring. Some shops use it, others just try to connect directly to the wiring. It would be on your receipt, since it's an expensive unit. Many shops use the unit made by Peripheral Electronics, it's model number GMCO.

If they didn't use it, that could be one of the reasons. If they didn't use it, and you no longer have the internal warning chimes (like door open, no seatbelt, fob in car, etc), then they didn't really know what they were doing. When you start the car up, there should be tones from the GMCO adaptor. If you're just getting buzzing, either it's a faulty adaptor, or no adaptor and a weird hookup of the stereo.

If they did use it, the immediate question to ask them is - did they use the low level outputs of the Kenwood, or did they hook it up with the speaker outputs of the stereo? If they said the speaker level outputs, ask them if they knew the car has a built in amplifier? If they didn't use the low level outputs, and they didn't remove the amplifier (and rewire the speakers to the deck instead of the amp), they didn't hook it up correctly.

The base stereo has a built in amplifier, which is designed to take a low level input. If you use a high level input, you overdrive the inputs on the amp, and that will cause the crackling sound you describe. At half volume unless there's something wrong with the stereo, you shouldn't be hearing the sound you describe. But it would definitely do it if the speaker level outputs of the deck are overdriving the amplifier inputs.

One of the problems is the instructions for many of the adaptors (and I've got to assume the installation guides) are wrong for the Vettes. Often for the base (non-Bose) stereo, the instructions don't indicate the presence of an amplifier.

Good luck with this!

 

I would check the installation. Sounds like there is a problem there

 

Thanks very much for the info...I just got back in town & will be following up with these questions to the insaller. Is the adapter the same thing as a wiring harness? I did get charged for that but no adapter as far as I can see on my receipt.

 

Take it back to them again and demand they fix it! They did something wrong! If they can't fix it, then tell them you want everything removed and your money back, you shouldn't have to pay $2000 for something that sounds so terrible.