I know this must be a very common problem, but I haven’t found a solution that will work for me, so here it goes:
I have an Etherwave Standard Theremin. I would have problems in different locations while setting it up, specially because here in Brazil almost none of the power outlets are grounded.
When I lived in my old place, we had no grounding anywhere, but it was a big apartment. Usually, what would work is I’d plug the Etherwave into one outlet, and then try to plug the amp in another room’s outlet until I could get sound. If I’d plug both on the same outlet, or outlets in the same room, it would not work.
Now I moved to a one-room apartment (really, it is just one room). So you can see my problem here. No combination of outlets in my apartment works.
I was wondering if any of you guys could point me to a possible solution. Maybe improvise some grounding somehow, or use some sort of adapter that would solve this problem.
Any help is greatly appreciated. I will be living in this ‘hole’ 
for at least another 4 months, and I really need to practice at home.
Also, if any further information would help, I can provide it.
thanks in advance!