Hi vsky,
I'd like to offer our perspective: The rotary encoder in the m920 is the same part that we've used for over 10 years in the m902, m903, m904, m905, m906 and m802. Many of these products are used full-time in production environments. We've found this part to be the best choice because it is the most robust. We occasionally get m906 remote-controls in for service that need new encoders but these are 10 year old units from busy studios. Note that this is not a potentiometer. As Michgelsen points out, the digitally controlled attenuator provides channel matching that's impossible with a pot. Performance does not suffer from aging as with pots. There is some play in the encoder's shaft. We acknowledge that one may reasonably prefer less play in the shaft. You won't find a more reliable alternative. We take great care in selecting parts for user controls. A consistent complaint about the m902 was that the input select switch had too much play. When redesigned that product (m903 and now m920), we chose a better feeling switch. It is much more expensive and doesn't perform the function any better. But, we were able to improve the tactile experience without compromising performance.
We haven't previously received complaints about the feel of the rotary encoder, but we do identify that folks will have a different tolerance for this kind of thing. Rest assured this is a high quality part. We're really sorry you're not happy with the feel of the it, and if you believe yours is broken or unnecessarily sloppy we are happy to take a look at it and fix it under warranty if need be.
thanks, Caleb