I purchased a Marshall MG30FX amp (Serial Number V011AA674U) Musician's Friend. When I power on the amp in clean mode I get the Chorus effect even when FX is turned off. I returned the amp to Musicians Friend and got a replacement. Same problem. Eventually, I discovered that turning the FX knob past the Chorus setting then back to "Off" shuts off the Chorus effect. Has anyone else experienced that problem? Thanks for your help.
It's not an issue, it's a feature of this amp. Switch it to clean channel, turn of the chorus and press STORE button.
I strongly recommend to read the maual. If you don't have it, dowload pdf version from marshall . com / amps / products / amps / mg-gold / mg30fx (remove all spaces from this link).