One way to reduce contact bounce on Creality Display w/o software

[Ergonomicmike]

When I first received my Ender 3 V2, I noticed a lot of contact bounce in the rotary knob of the Display.

Well, not so much bounce as missed reports. (Skipping.)

I notice in the Marlin code attempts to address problems with the rotary switch. E.g., I saw something about an EMI Filter.

Whether there is EMI or not, I used to see this behavior in my aircraft radios. The fix was simple. It's mechanical.

There is a product called ACF-50. Take the back off of your Display and drip (or spray) a little bit of ACF-50 on the contacts of the rotary switch. That solved the skipping problem for me.