There are lots of electronics shops across the country that do repairs on car stereo amplifiers. Unfortunately repair costs often start at about $100 and go up from there. So sometimes it’s not cost-effective to have the amp fixed when you can buy a new replacement for around the same price as a repair. Look for a repair shop that will give you a free estimate before the repair is done. If you do have it fixed, try to use a shop that’s certified by Sony. But some repair shops do excellent work even if they aren’t factory certified for your brand of equipment. Check online reviews and word-of-mouth from previous customers.