I stopped waiting and replaced all the knobs instead. Used the recommended detended Alps encoders, and now all works fine. The firmware, though, is clearly made for un-detended knobs, so a bit annoying operation on some of the parameters, that are changing between discrete options. There you have to turn the knobs 3-4 clicks before they change, which means the click is suddenly useless and just in the way. I have asked if they have a fw version for detended knobs, now they recommend it but I'm afraid they dont.