Both of my PWC's had dead batteries after not using them for a month. After pulling them out, charging back up, and installing them again, same thing happened a month later. Repeated the pull/charge/install process and noticed sparks when connecting the power lines to the battery. With everything turned off, is there still something pulling current? ... ok .. that was a rhetorical question .. of course there is .. it's the audio system. How is this even considered good/acceptable engineering to constantly draw power when turned off? I suspect the ECU is pulling some current as well when in the off state but have not metered it to verify. I called Yamaha Corporation in Kennesaw, GA and the rep told me this battery drain is very normal for PWCs; although, there is nothing in the Owner's Manual specifically addressing the battery drain issue. Wanted to get feedback from owners with the OEM audio system on what they have done to mitigate Yamaha's flawed power management system. Do you just keep a 10mm socket/Philips screwdriver handy to disconnect the battery terminals every time you park your skis? Or did you install a quick disconnect on either the hot or ground cables to prevent battery drain when not in use?