I have an Infinity IM 1.2S which I have had for about six years. I've had it in to service once already with a smoked amplifier. Now I get no sound at all. It powers up, gets signal (the volume knob goes from lit red to lit green when the sub is getting signal) but has no output. I would very much like to get inside and poke around, to see if there is a connection that is broken, but I cannot even get into the cabinet. Any suggestions?