Thanks! So I'll contact the support... Hope it won't get to complicated because I live in Germany...
For what it's worth, I'm in Canada and I had to contact DSI for my OB6, and REV2, and both times the response was quick and helpful. I'm currently awaiting to receive parts for my REV2 (defective encoders).
BTW, I also have bad experiences in general with encoders in the past, from many different manufacturers. They always seem to fail at some point, either due to getting worn down, or dirty.
But in the case of the REV2, I suspect it might also have to do with a feature called "software acceleration", in which the OS checks the speed at which values are being changed by the encoder, and if it's turned more rapidly, the software will skip values to get from one end to the other of the whole range. And if an encoder is "scratchy" between steps, it might fool the system in thinking that the encoder is turned rapidly, when in fact it is not, and trigger the value skipping inadvertently... ? (just guessing, but that's what it looks like to me)