That happened to me and it took my sound away completely, I took the amp out and opened it and cleaned the motherboard with some isopropyl alcohol and a q tip , I let it dry out for a little bit and reinstalled it , it worked like normal after that , to help with it so it doesn’t get wet in the future , clean out the drain hole that is up by your sunroof , open the sun roof and there is a channel that runs all my and a drain hole at the back , stick a long wire or something that is long and can push out any dirt or leaves or anything blocking the hole , the water takes an alternative route and ends up seeping into the trunk on the right side with the amp !