I have had the same issue as they come lose when you tow and after a while on the boat. I check my spealers and tighten them every couple hours. I might try some Blue lock tight as I do not plan on taking them off very often. I had one speaker that had a bad connection and was cutting out and I took that to Semper and they replaced the cable and I have no problems since. I think the design is bad on the conector bolt. Will be at Pine Flat this afternoon for a little riding and surfing? Hope to see your boat soon.