Update :
I managed to fix it myself after checking the schematics from the Hackabrute's website. Indeed, IN MY CASE (maybe not yours, do it at your own risk) after checking the signal path of the LFO wave at different testpoints, I realised that the signal was alive just before entering the LFO amount knob (TP85 is the last test point before that), in my case, the LFO amount potentiometer was dead. Fortunately for us, all the pots on the front board are doubled, which leaves us with three pins (+ the dummy one) that are not used on each pot !
To fix my issue, I simply soldered the following LFO AMT pins together (check attachment) :
- IN1 to IN2
- OUT1 to OUT2
- GND1 to GND2
My MicroBrute's LFO is back from the dead (both PITCH and JACK CV OUT) !!!