3 weeks ago, I installed a GMG exhaust on my 07 RS4 by a local shop. It sounded fantastic! However, over the last week I have noticed a substantial decrease in volume (sound) from the exhaust. It almost sounds like the car is stock again. I contacted GMG and have never heard of such as problem. It's definitely not me getting used to the sound, and have had friends even comment on the lack of it. Anyone have any ideas? Thanks in advance!

Packing in muffler may have come loose and moved to back of muffler. This is possible on some designs that do not have a pipe inside the muffler. I'm assuming the GMG muffler is built without an internal pipe. If it DOES have an internal pipe, this is unlikely.

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