It is now nearly a month since your last email and my subsequent reply has not been acknowledged (both below).
I feel I have been very patient considering that you have had the amp since the end of April. I do not understand what the current delay is in view of your previous assurance that it was fully tested by 19 August.
I would appreciate some action to finish any outstanding work and get it back to me.
So as of 19 August the amp was all but ready, but more weeks have gone by with no news.
Well suddenly it looks like we're into a slightly different problem - see part 39.