check your battery, make sure its charged all the way and then i guess check all your power and ground wires. I don't really know what to say to you about this really. i've never heard of it so, i'm not going to be much help

 

you said youve already installed a new battery, however its possible for them to go bad almost immediately...my battery was less then 6 months old and somehow got a dead cell and i had to replace it....just something to try

 

True "BlazerGuy" haha, aka Derek, you sometimes just get crap batteries and what not. i need to replace mine soon with a deep cycle one or something similar. with just 500 watts of "pure" JL power getting thrown through a sub, my battery gauge dips when i'm doing 70