No, that’s not normal behavior. The encoders should respond similarly to how they do on your OT.
If you’ve had some practice soldering, elektron machines are pretty easy to work on and the replacement parts are cheap… However, I wouldn’t recommend that to someone with no prior soldering experience - in that case, I’d recommend taking it to a local repair shop.
[edited] I just remembered this thread below, you can try this if you’re feeling adventurous:
Octatrack MKI encoder issue - jumping values - Elektron Gear / Octatrack - Elektronauts