Took in the Prius for a subwoofer/amp install and it works perfect. Went to another shop in Dallas for a HU/door speaker replacement. Went with a Pioneer 501EX https://www.pioneerelectronics.com/PUSA/Car/DVD+Receivers/AVH-501EX and the next day p/u the car. I used a Mexican shop on Harry Hines for the second install and it was really bad. The right channel was coming out of the left speakers, the system sometimes turns on with a loud buzzing sound and I have to immediately shut it off and re-start the car...this happens 1-7 times a week. The bass now is making weird pulsating noises. Now all the door speakers sound blown. I don't want to go back there since they are obviously not good installers but don't want to pay and arm and a leg for a real installer to fix it. Any recommendations of a mid-ranged priced audio guy in Dallas that knows how to properly use a multi-meter and knows what he is doing? Even an independent guy would be fine with me. Thanks! It sounds like something is grounding out and the voltages are hooked up wrong if that's possible.