I feel like I have wasted my well earned money on this line 6 spider iv 120 and fbv mkii! there is popping when changing channels and volumes on presets are at eardrum bursting levels. I see this is a common problem and cant find a fix i wish i had known about these problems before I bought this amp such a pity i really enjoy the tones........will be posting this on other websites in hope for a fix! :unsure: :angry: :(