Hi to all
thanks for replying.
Well after spending a couple of hours around the board, i've figured out what was the problem, and really, its even worst for the repair center at this point...
The problem was a non touching solder joint just after the dc plug on the ground pin, just before the first component on the power supply line...
Did the tech dont realize? or for them is easy to tell the customers "trow in the trash", charge the fee and let buy a new pedalboard?
If the schematics its available it will be helpfull, i know at least 4/5 guys with the same multifx that have got the same reply from the repair shop...