I installed a Sony head unit in my daughter's 06' Pontiac Vibe. It had a factory amp and sub woofer. Whenever I turned on the head unit, a loud pop would come from the speakers. So loud that I was surprised the speakers didn't blow. I read about the SOEM-4 to perhaps fix the problem. I bought it and it worked, the pops stopped. However, a buzzing sound appeared when I started the car. The buzz varied with the speed of the engine. I moved the SOEM-4 to another spot in the dash and the buzz stopped. Overall, I was happy with the product.
0 of 0 found this helpful