yea thats not bad i guess my voltage isnt bad at idle at the amp lowest it goes to with lights on is 11.75 for a split second but for the most of the time it hags around 12.25-12.5 and thats with a zx1500.1 and a zx850.4 only using 2 of the 4 channels so around 2krms and i only got stock battery upfront gold duralast with the 2 grounds done on the big 3 and a stinger spv70 in the back with a stock 130amp alt.
might have to try the extra frame ground i have engine noise but its prob cheap rcas right beside the power wire