Sorry I didnt reply to your PM Avram, I only just noticed it today.
Both channels on my Microbass 2 are dead quiet. There must've been something not right with yours.
With a great bass, like your Thumb, the Microbass 2 isnt really going to improve it's tone, but plug in a completely passive P-bass & man, it really shines.This is where this pedal really shines, but we both know how many P-bass's we have.
I use it mainly because it brings together in one unit, every possible feature I could ever hope to want or need. Like the A/B box, splitter/ blender,pre/post DI, tube sim, ground lift, -10 dB, headfone amp, you know the drill. Swiss army knife of pedals etc etc. It replaces the need for separate, individual devices in one quality unit, with the advantage of being powered in every possible way, from battery, mains to phantom power.
Rather than actually improve a great quality basses tones, it more or less makes it more versatile, rather than improves it.
It's the one pedal I personally couldnt live without.
I find I normally just plug in & set everything flat, but if the need arises for any of it's features, they're there.
Cheers mate.