He apparently has the same issue but without a motor though.
One could say that, if he put a motor platter in it, would that anomaly cause his motor to speed up or slow down?
I really like the player and was even thinking about picking up the non motor version.
But gotta wait to see what the next fw update brings.
Can you guts post your user prefs. One I’m looking into is the instant start setting as something that causes weird things. Mine was off
I doubt it. I have three non-Ms (and have had 4 units) and none of them do (or have done) that. Both my Ms do the motor speed up thing when they get hot but before the fans turn on. Sevenkami needs to make a video of his issue before I assume this is the same problem. Grounding issues can cause the touch to flutter and a track can seemingly slow-down, for instance. And if you turn the motor off when the speed up happens on the M, the track returns to normal speed.
Replied with a video (post is pending moderation). Track slowed down instead of speeding up (cause layer A BPM was lower than the layer B track) and then speeds back to normal. On a non-M prime.
Link:
Edit that post I’m responding to and put the link in there.
I don’t know. Maybe it does have something to do with layer and soft takeover. After all, returning to zero pitch does fix it, but it’s definitely causing the motor to rev up on the M and that’s where the speed detection is coming from.
I don’t know what I’m supposed to be seeing there.
Looks like you’ve got sync in use. Yes?
I see your pitch fader is at zero.
I see the soft takeover light on indicating, I guess, the background layer pitch is less than zero. They appear to have several soft takeover glitches still where it lights up and shouldn’t.
I don’t know for sure whether any track is changing speed from the video.
Is there a slight slow down occuring on the playing background layer when you first play the layer you’re on beginning at about 4.5 seconds?
Yeah, that’s it. The track in Layer A (which is audible) slows down when i press play on Layer B (inaudible) while master is blinking for no reason then speeds back up to normal. If the speed difference is the other way around, it will shortly speed up then go back to normal.
I don’t get the video also.
The track your start becomes an immediate master? What happened to the track already playing?
No, the other layer (A) is the master, which is playing (audible). Before i started filming i switched to Layer B. You see me load the track and press play on Layer B. Then it happens.
Sorry for the unclear video. It was just a quick load up two tracks on one player and upload. 
Yes but I don’t understand why layer B becomes master the instant you press play. Layer A should still be the master until the channel fader is down or until the track is paused or cued.
Don’t use sync so it’s new for me.
I suspect this is a different glitch having to do with soft takeover, sync, and layer, probably having to do with some kind of interval between when you start playing the track and when it really knows what the bpm is it’s supposed to be using or something. They do have a lot of issues with soft takeover, and obviously sync requires the analysis to be working in a timely fashion. You can see in my video that the speed up in that glitch is indefinite until you either turn the motor off or move the fader to zero, and the background layer was not the layer you were hearing. It wasn’t even playing at the time.
If you follow the instructional soft takeover arrow, does the speed change resolve sooner? Does going to the playing background layer and doing anything resolve it sooner, too? If you do nothing, does it resolve on its own and when?
It is good that your bug is repeatable and predictable in that you can duplicate it at-will.
Try without master and/or sync off (non-M).
This happened to me when I tried out the sync feature. I assumed because I only have one deck that it would be hard for the deck to assign master to the layer that you want. I seems sometimes both are master or both are not.
So far I see that bringing the pitch fader back to zero kinda avoids a lot of the issues so I’ll roll with it.
I wonder if we’re giving Denon a good laugh by watching us trying to firgue out our issues.
Well this kinda gives me the fear about the upcoming arrival of my SC5000m setup. (ordered in December and out of stock in uk till mid March) I need to trust the basic fundamentals of my gear 100% when playing live.
I’d sure feel more confident in my investment if someone from Denon at least said, “we’ve got this, we hear you, we have identified/reproduced the issue, and are working on a fix to be delivered within x window (or it requires a hardware revision)”
With all due respect, even though it’s intermittent, the issue seems so fundamental and potentially undermines customer confidence so much, shouldn’t this be a high priority?
Fingers crossed a fix is bundled in with the Prime4 era of SC5000 firmware
Man, If there’s no solution or statement on this and it happens to me within my return window, I’m sad to say i’ll be looking elsewhere. I need to trust my gear on the fundamentals. The fancy icing can have the odd bug in it but the core needs to be 100% predictable.
Seeing Denon staff post all over on more frivolous threads, yet ignore this makes me worry about the investment I just made.
I could probably buy a little car for the price of the full bells and whistles setup, if that randomly sped up out of control at an inopportune moment, I sure wouldn’t be keeping it!
There are bugs but if you read you’ll find kind of the do’s and don’ts. I’ll be bringing my deck out this weekend but will be using it through traktor’s soft mixer just in case I need to switch quickly at the press of the button.
I don’t suppose anyone here tried tagging any Denon staff members to help make them aware of the thread? It’s quite possible they just didn’t see it…
I would suggest not bad-mouthing the staff until you ascertain why they haven’t replied. Here, I’ll even help by doing what you haven’t - tagging the staff.
I must say, I find the lack of responsiveness from Denon DJ staff on significant issues is worrying me.
Roll back a few weeks, we invested in a single SC5000M for testing/comparison with the view that if all went as expected, we would buy 9 more players instead of renewing our older Pioneer CDJ 2000/NXS with NXS2 players…
However, this issue and others such as the high frequency roll off, coupled with the glaring missing functions in Engine Prime… we are having second thoughts and are now pricing up NXS2 stock again.
When we see InMusic’s very proactive response to the Rane Twelve issues - all affected players taken in, repaired and returned … and a high level of interaction from Rane team members on the forum, I feel disappointed by the Denon team in comparison.
The high frequency roll off is corrected in the next firmware update don’t worries guys ! 
The problem Denon really need need to catch up with Pioneer and it’s not normal we wait since september 2018 for a new update for Engine Prime, c’mon it’s 2019 major thing are missing for Prime, and why after 2 years we don’t have :
and I can continue 
I wanted to see if i could reproduce this bug in another way. Played a track on Layer A (sync and quantize on) and forward-spun the track in the other Layer. Layer A went nuts (speed up) and back to normal.
Forgot to film or record it though. 
If i disable sync and quantize none of this happens. Looks like software to me. Denon, pls.