Hi! My DT50 makes hard noise when I switch between the channels. If switching within one Amp modell configuration with just two different Tone / Gain setings, no creacklings noticeable. If I switch from e.g. Class A to Class B the "plob" is unacceptable. Also while switching e.g. within Class A between Modell II and III the noise is far to loud. BUT, if I switch for 5 or 6 times in succession the noise is gone. This dooes not work for all combinations but for some. If I wait 1 or two minutes without switching the "plobs" come back while switching. Seems like something (capasitor or other component) will be charged. I can not use the amp on stage (playing loud) because these plops gets realy loud. Any suggestion? I am not clueless if it comes to electronics but if this is a general feature it makes no sense to start searching. This is not tube related!