Unfortunately it sounds like issues in the MP1, I'm not convinced it's a transformer issue or you'd have no power at all. Do the tubes light up (glow?), if so, my guess is it's not the tranny (MDRT is still a good idea though). Again more MJMP/Sparker territory Get your tech to check it out, schematics etc on here to assist. If you want to chase it through yourself (no doubt will need a multimeter), MJMP can talk you through it.
. Thanks , I spoke with him about it this afternoon , he's worked on them in the past so hopefully he can solve the problem . I'll give him the suggestions you guys have offered and I told him about the schematics . The unit works fine when the ss presets are called up , but no functioning distortion presets . I get clean and effected clean only , as I also said I, it must be turned on twice as the self diagnostic does not reinitialize it . Yes the tubes are heating , I put in a new set with the same results , no difference with the tube change .