I know it’s been awhile but I guess I missed this post.
My muse has had the tuning issue and I’ve been working with my vendor for some time - Moog’s support sort of stalled after the hurricane, I’ve re-touched my support ticket with them (now two months old) to see if they have anything to say.
What’s happening: tuning sort of sucks.
After a full tune from cold (~1 hr) it takes a couple quick tunes to be good, but soon two voices (on osc 1) start to drift, 3 and 7 in my case. Once it’s “stable” over 40c and a quick tune or two are run it will be in-tune ish, though “stable” takes an hour or more to reach. In 10-15 minutes the voices will start to drift again, and after awhile (dozens of quicktunes and several power cycles - think a week or so) the quicktunes can actually make tuning worse, and you get wild 12-17 cents out of tune voices. The only real fix to that is another full tune. I’ve tried a tune warm too just to see if that changed anything, it didn’t.
Moog told my vendor they thought it might be hardware and I’m probably getting a replacement unit, but it really seems like software to me based on that description.
I don’t think 90 minutes to reach stable is reasonable for a polysynth, or that it should require so many manual quick tunes after reaching stable, but that’s me.