I have an old epiphone tube combo that I converted into a head. 2 12ax7's (one for trem), one el84 and a 6x4 rectifier. I recently moved acroos the country. I was, of course, very careful with all of my gear. Since living in my new home I have noticed that the amp buzzes more then iit used to. It has a two prong power chord and the on switch is also a "polarity" switch (when switched it can reduce the buzz). When I turn down my guitars tone knob all the way the buzz is all but eliminated. When I physically touch the metal knobs on the amp the buzz is reduced. Adjusting the tone and level knobs on the amp can dial out some buzzing but makes the tone unusable (same goes for the knobs on my guitar). I have checked the cables, switched the power tube and V1 with new tubes and tried different guitars. Still, the buzz remains. I am concerned because I want to start recording at home but the buzz is so loud that I can't use my amp (I know about the alternatives but want to mic my amps). My other amp is at a friends house and I noticed that the slight buzz it had in my home has all but disappeared when plugged in over there. Any help is appreciated. It seems like it could be a grounding issue (could a power conditioner help?). I don't really kow enough to say .