I have an alpine 1541D which ive had for just over a year, its running off a kenwood kac929 which isnt meant to be stable at 2ohms so have been running it at 8ohms(sub 500rms, amp 450rms at 4ohms but is at 8 so will be less). It ran fine until i took it out of my car and left it for a few months when i refitted it, it has now been in there for two and a half months, it sounds as if it is muted and it has low volume without being set to +6/12db and then it sounds terrible. I have tested on different amp and is the same. Have tried wiring a voil coil per channel and the same happened. Have usually had the headunit at 70% and amp at around half. Any suggestions or is it a lost cause?