Hey there /diy/, I was wondering if someone could help me figuring

Take it apart and have a look. It could be a cracked solder joint. Faders don't typically just stop working, they just get scratchy, but take you should check it with a multimeter just in case.

>>1054044
Will try, thanks! Try to open it once, but it was a one single circuit card so I didn't do anything at all

>>1054048
Dig deeper son. Do you own a multimeter? Home depot/Lowes have them in the electrical Dept if you want one today, else order one online if it can wait. An el cheapo will work for this low voltage DC stuff, but you need one that can do DC voltage and resistance(ohms). Google 'ohms symbol's if you dont know what to look for.

>>1054044
Not sure how exactly the Aira series is put together, but a lot of analog modelling gear relies on an ADC after analog pots, and a tiny bit of scratchiness or noise will screw up their readings bad. Late 90s lower-end Korg gear was like that.

>>1054040
those are pretty new, see if it's still under warranty by roland