# USB Audio Problem



## Dragonsys (May 27, 2013)

might be an does it only do this with audio on USB, or does the radio only play out the left side as well?


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## obermd (Mar 3, 2012)

How many miles on this car? If it's below 36K it should still be under the bumper to bumper warranty.


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## emanon9297 (Oct 10, 2012)

It actually sounds like the usb port is what the problem is. If the audio/cd/aux and bt play fine and it only happens with the usb then 
I would start there first.


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## obermd (Mar 3, 2012)

Rereading OPs issue I don't think replacing the On-Star module behind the glove box is where the problem lies. OP - what stereo/navigation options do you have?


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## Dragonsys (May 27, 2013)

Welcome to the Forums BTW


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## texascruise (Oct 8, 2013)

Thanks all for the responses. Everything is all stock. Used car was originally from a rental agency and is no longer under bumper-to-bumper warranty. I was thinking USB port also, but I can still read the songs just fine and they show up on the display perfectly. If anyone had a wiring diagram, that'd be great. My guess would be the port connects to the module somewhere, and then there is a separate audio connection out somewhere? I feel so lost with all of this.


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## obermd (Mar 3, 2012)

texascruise - the answer to the connections depends on what your stereo/navigation options are. Here are the options:

Base Stereo - no navigation
Base Stereo - navigation
Pioneer Stereo - no navigation
Pioneer Stereo - navigation

If you have speakers on the rear deck you have the Pioneer system.


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## NYCruizer (Jul 10, 2013)

The fact that ANY music is being played from the USB stick disproves the theory that it has anything to with the USB circuit. OP, you state that you tried two different USB sticks, however you don't state that you tested them on another system, have you played the music from those USB sticks on another system to rule out that the tracks themselves were encoded on both channels?


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## obermd (Mar 3, 2012)

If OP has the base radio without navigation it could be a faulty PDIM. This is why I asked for the stereo/navigation option on his car.


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## texascruise (Oct 8, 2013)

Pioneer Stereo with no navigation.


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## obermd (Mar 3, 2012)

Your USB/Aux cable(s) plug directly into the back of the radio. I'd pull the radio and ensure they are firmly connected.


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## NYCruizer (Jul 10, 2013)

obermd said:


> Your USB/Aux cable(s) plug directly into the back of the radio. I'd pull the radio and ensure they are firmly connected.


If it were the USB nothing would be playing at all - the USB simply streams a file byte by byte, there's either a chip or software that decodes the file and re-encodes it for the audio system. USB couldn't possibly interfere with a single channel from an encoded file, it's essentially all or nothing with serial communications. This leaves a) the file wasn't coded on one channel, b) the coder/decoder is faulty d) the wiring from the coder to the audio is faulty or c) the audio system.


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## obermd (Mar 3, 2012)

I've seen lose USB connections do strange things. I understand that USB is basically a serial connection, but it's still worth checking. It's also a relatively easy check to do.


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## texascruise (Oct 8, 2013)

Thanks for the advice, all. I will hopefully be able to check the system this weekend and give an update. Does anyone have tips on radio disassembly instructions or should I just look up a step-by-step on YouTube or here on the forum?


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