I agree with Mojo as you are the first person to claim the M3s are more forward with the mids and highs where as everyone else has it the other way, the M3s are more laid back and the M80s are more forward. It really does sound like there might be something wrong with the M80s

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70