Got a new Little Big Muff for Christmas. Wrong power supply was bought for it but pedal worked great using the internal battery w light coming on ok. Yesterday plugged in and no power/no effects/no light.

Pedal off lets bypass work but pedal on there is no output through amp.

Tried replacing battery but no result and original battery checked out as still working. No connection issues visible on board when replacing battery.

Is there an obvious answer I’m not seeing? New to guitar pedals. Could use some help. Cheers.