Hi Rich!
Thanks for the answers and the tips.
I will check IN and OUT jack connectors on the B200s: I've to pull it out the flight case and clean them with a good spray.
Channel B always work fine, Channel A sometimes starts having "issues" if I disconnect cables...probably IN or OUT jack has some dirt inside.
Today I did a test with mono setup and, at first attempt, Channel A was 100% muted: no sound at all.
Then I disconnected and re-connected cables and it started working again fine with no problems.
By the way...I love it in stereo config!
Pots of both channels are not noisy or scratchy at all, they are smooth all along their stroke and both channels have the same level at each pots setting.
I also like how the B200s works in stereo at 16 ohm: it should deliver 50W+50W and it's perfect with the 80W+80W speakers of the Blackstar cabinet.
As I wrote in my MP-1's thread, I just regret I cannot crank B200s volumes up over 7...
At the moment I use both channels at 4-5 and I set sound level through MP-1 and GMaj: in this way I can get very good tones even at low volume.
Another thing I've noticed is that my B200s doesn't get hot at all...
I've nailed the MP-1 in flight case's top position, with GMaj between it and the B200s...there's some little space among all the units and air can circulate in a good way through the case, but the GMaj doesn't get hot due to B200s...
Maybe this depends from B200s being used at home levels and underpowered due to 16 ohm impedance of cabinet.
A very good power amp, a very good choice.
Thanks for your suggestions about it, guys!