Recently saw the Marantz Model 50 at bestbuy and was impressed by the sound and features except for the terrible volume control. Turning the volume knob feels like they got axle grease in there. And the knob has no texture to it, so you need a firm grip on it to adjust volume. Too bad because the rest of the unit is some nice kit.
Not sure why you would ever use the manual knob. I either use my phone via heos or the remote. There is a legitimate complaint with the remote in that it’s so minimal and sleek it’s very hard to find the volume control buttons I find. That said, my volume knob broke off in mysterious circumstances, though my dealer said they could probably get it repaired under the 5 year warranty. The 40n is built like a tank so maybe the stuffiness is just part of that feel.
Digital knobs. The 40 feels as good as or better than most devices using digital knobs.