I upgraded to 3.7 yesterday and the tempo faders don't respect positions. I reverted to 3.5.3 and everything is back to normal. bad time for N.i. developers......
I have been on this for a very long while already but I was not taken likely about it. Thank you for mentioning this. I have beeeeeeen experiencing this, NOT only on my S3 unit, but using the Pioneer CdJ's as well. It is as if the tempo has a mind of its own & decides to to jump tempo, in my case, reverts back to the track's tempo.
I hope this thread of yours gets attention.
https://community.native-instruments.com/discussion/5559/traktor-pro-3-6-0-325-bug-tempo-reset#latest