I have have a CR 2020 that was not working when I bought it. I've done the service mods. Checked all the transistiors. Each time I power it up the the B+ fuse on one Amp board blows and short out both TR611 and TR613. So far I've shorted 2 of each. Not shure what is causing the shorts. Thanks Avonic, I've read your threads on yammies for the last year. Hope to you and the Audiokarma family can help as I've hit the wall on this repair. Need some direction:scratch2: