My 100hdfx has a problem switching channels. Both overdrive channels work fine but the clean channel is none existant. If you switch it to the clean channel and turn it up all the way you can faintly here a guitar but it is from the overdrive channel. Any help?
Music - Marshall - MG100HDFX 100-Watt Amplifier Head
Answers & Comments
Have you tried the footswitch to change channels. also. my amp has to be in channel 2 position (with the button on the head) before i can use the footswitch. sometimes the input/footswitch jack wears out and you need to bend the internal tip/ring tabs of the jack to make better contact. also like on my fender amp, i had just a standard mono instrument cable going to my footswitch and it was acting wierd cause it needed a stereo instrument cable. one last thing on the grounding resistors on the pcb, they get hot and break the solder welds which messes with all sorts of stuff in amps. usually look like sugar cubes , cement resistor. 5watt usually under 1k ohm. check for bad solder welds on the pcb where the big resistors are and the switches/buttons and at the footswitch. there may be a bad ic or transistor for the channel swithing