Distortion channel

[RG1550GXWB-WM Ltd Edition]

Hi! I've got a Marshall MG100DFX and I love its sound (with the fdd sistem that well emulates a full valve amp).
Since 1 week I've got problems with its distortion channel: I sound for a while, but then the sound come and goes (it has unbelievable decreases of volume)! I've tried with changing cables, but it isn't the problem! It cannot be a problem of all the amp, because on the clean channel it works! It cannot be a problem of the guitar, because I've put the jack in another amp and it works, so...what could be the problem?
I thank you in advance!

[red5]

The MGs seem to be a bit cheaply made. There is either bad component in the amp or a wire that was way too thin for the current it needs to transfer that got melted (as the MG wont melt a normal wire as they don't use that much power). A toasted wire is often a cause of this. Sometimes bad transistor or capacitors as well may be the culprit, and I would normally say a bad transformer could be too but if it works with one channel and not the other, then you're good there.

[RG1550GXWB-WM Ltd Edition]

Thanks for the reply red5!
Yesterday evening I've tried to connect in stranger ways guitar, Bad Horsie 2 and Marshall and I've seen that connecting the wah in the send-return instead of between guitar and amp, it doesn't make that problems on the distortion channel! Perhaps I've found a solution!
I love its sound!