I repair car amps for a living and my prices are the chepest in the USA if an amp needs to be sent to me, plus shipping. I get a lot of amps to repair from this site. Sound like you might have to low of an ohms issue. If not I would have to have to look at it. I don't charge a bench fee and give a 90 warranty. I have the same amp in my collection. My prices also rarely exceed $60 to $80, something like yours would be around $40 or $50 plus shipping if you need to ship it to me. I have been doing this for 17 years and have'nt ha a complaint once. I also fix things in amps I see that might need fixing for free. People ask me why I do'nt charge more or fix things for free, is because I'm not hard up for money and I want to help my fellow car audio enthusiests. Let me know if you need my haelp. I will try to help you online first before we need to go further.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/mark_b53a7494531bf96d