Heres my system layout ((Pioneer AVH-P6300BT --- Rockford Fosgate Power Series 600.4AB for the highs and mids & a 1500.1BD for the lows --- 3 10" Alpine Type R Subs --- For the mids and highs I have 4 Pairs of JL Audio C5 Components, thats 1 pair for each channel on the 600.4 --- Electrical= 2 Optima Yellow Tops in cab 1 Optima Red Top under hood, all 0/1 AWG Kicker OXY Free Silver Tinned wiring with a IRAGGI 350 AMP Alt to back it all up. RCA cables are jl audio top of the line cables ran clear from any power wire. Everything is recently bought nothing is older than 4 months! My highs and mids starting cutting out at higher volumes and cutting back in when i turn the volume down, whilst this is going on the bass (never) cuts out. At first i thought it was the amp but after i exchanged the amp for a new one i realized it wasnt the amp. All thats left is the head unit. Is it possible that i could have blown out something in the head unit?? BTW i have the HU powering no speakers, just sending signals to the amps. Please help, maybe i overlooked something.