Repair Shop In VA / Washington DC - Rec Please

One of the very best repair shops in the DC area, with a good reputation for the whole eastern part of the country is Music Technology, in Springfield Va.  The head honcho, Bill Thalmann is very good with both solid state and tube gear.  

I have not dealt with HiFi Heaven in Falls Church Virginia, but, they too have a good reputation in the area.

+1 for Music Technology.

DejaVu Audio outside of Washington DC is another option.

I have used Pro-tech in Silver Spring MD on a Classe amp.  They are certified for many brands including Mcintosh.