Stereo shutting off?

Last I year I put in 2 pairs of samson S7hds with the 1K harpoon amp. They worked great all last summer and the first month of this year with no problems. Now the speakers, amp and head unit will shut off right when I turn the stereo on. It started out where they would just shut off when I turned them up loud like they were not getting enough power. Now whenever I turn on the stereo, the display lights up on the head unit and immediately shuts off. Even when I turn the volume all the way down on the tower speakers and it is just the cabin speakers, the stereo will still turn off. I also have another amp and subwoofer that was stock in the boat and everything shuts off when I turn on the stereo. I have charged the battery's and checked the connections on the battery and neither have fixed the problem. Anyone have any suggestions on what to try next?