I’ve not noticed this on my fates…
Is it only on one particular encoder, or all of them?
(if you have install Orac, does it happen there as well, or just in the norns software?)
which rPI are you using? 3b, 3b+ or 4?
are you on the latest norns software version?
(monome have tuned/improved the way the encoders have reacted over the various releases as some users had issues)
I’d personally think its most likely software, given it only happens at ‘speed’,
(though it could be a faulty encoder?)
if it’s on all encoders, its seems unlikely you would have multiple faulty encoders or soldering issues.
if it’s on one encoder, and its easy to do … I’d probably look over the solder joints, perhaps a dry joint -so just reflow them (heat it up joint again), also look at the header pins to the raspberry pi for same issue.