I got a Spider IV 15W amplifier that is pretty nice piece of hardware, but recently it has developed an issue where chorus/flanger gets turned on by itself. For example I have a clean tone without any effects enabled. For some reason chorus or flanger gets turned on even when no one is touching the amp. I did factory reset (hold Clean for 5-8secs while turning on the amp) and I've tried to rotate effect knobs from 0% to 100% and back to 0% for some time if it's defective knob but this isn't really helping. Any of you guys have any suggestions I could try to troubleshoot this problem?