Why is my deck doing this?

Ok i have a 2000 Chevy Cavalier and I installed a kenwood kdc-x592 deck in it. I installed the deck when I bought the car 2 years ago. Now today I got inside my door panel to tighten up some nuts and bolts that I could hear were loose. Now whenever I turn the volume up to a certain decibal the deck turns off and resets. Doesn’t go into protect mode, it just turns off and then right back on. Any ideas on what this might be or how to fix it?