For so long I had terrible sound quality even at low volumes. I thought it was the power supply, so I spent another 10€ to get a 5A one, but the quality remained the same. You might say, what do I expect from an amplifier at this price? I had previously bought another one for 8€, which you could use any 12-24v power supply with. It was just a small board where you would screw in the cables. That board had crystal clear sound all the way to the max. It was superior to this piece of junk.