Without USB / MIDI cable attached, bootup is “normal”.
Various flashes of buttons.
Between 7-12 seconds on logo and version text window.
With USB cable attached
same as above, BUT
there is a 5-10 second blank screen before completing bootup.
i.e. no blank screens when no cable attached
NB: I created a ticket with elektron an hour ago
This what I have fro Elektron support so far, I really hope it can sort out…
"Just a quick update. We think we soon have a solution that will make it possible for you to downgrade/upgrade the unit on your own and fix the problem. We’re very optimistic that this will work. Hold off on sending the unit if you prefer this solution. It should be ready in a few days.
"
MKI here, encoder F has become very laggy when turned quickly.
Didn’t notice before the upgrade so I’m quite sure it’s not hardware related.
I think I remember similar issues in some thread on older OS, anyone else experiencing weird behavior with encoders ?
test the encoders in test mode - then all are evaluated equally - you may have a failing encoder, or you may just be on a parameter for which gearing has been changed
Thx Avantronica, just did.
Didn’t know about test mode, funny thing.
Every encoders work fine, some have slight differences but F definitely isn’t the less responsive.
I still think it’s software related since it seems to happen on every parameters (didn’t check every machines)… When turned quickly the value doesn’t jump but only increases by 1 or 2, in test mode same action results in fine response.
What do you mean by “gearing has been changed” ?
the parameter acceleration or feel in a parameter may have been tweaked, so a familiar parameter may have seemed off compared to before - just a thought, the test mode is what I’d put most faith in, but if it seems off run it past support
compare in one of the modulation menus - e.g. Aftertouch (Fn+FLTR, then scroll down) - each row of encoders should feel the same there, so E through H should give a good comparison incorporating F
Hi guys,
Hope you’re fine & safe.
Sometimes, when I turn the unit ON, the LED flash but then nothing.
Then, when I push a pad it starts :
Is it a known issue ? Looks like yes but still, I would love to get feedback from the Elektron family 
Thank you very much
occasionally when I turn on the Rytm it does the same thing, i just switch it off and on again and it works… I honestly don’t think it’s something to worry about, unless it happens constantly…
It happened like 3 times today but it was the first time. I’ve opened a ticket.
I’m sure they will fix it but still, this and A4 … not super cool 
When it happens try to switch it off again
Wait 2 minutes and turn it on again
It happens on my AR Mk2 on 1.60
It did not happen on my 1.50
Will try thank you !
Again and again. This is not good, not good at all …
Anyone else has the same situation ?
You could try the calibration routine. You need to leave it on for a couple of hours so it gets to working temperature before doing it, though. What did Elektron say about it?
Not sure it has something to do with the calibration because when I turn it off and on again, it works normally (if it starts well).
They said that’s not a know issue and they’ll be back to me as I’ll probably have to return it.
Glad I got it new form Thomann but I’m pretty disapointed, the A4 bug then this… 
I think it says in the manual to only re-calibrate if instructed by support…
It happens to mine also occasionally may once every 20-30 starts,
it happened today, I switched it on and black screen…
i dont press the pads though and just switch it off and on and it normally starts ok…
it doesnt seem to bother me because it always starts after power off, and its got 3 year warranty…
but I do think if it concerns you @Carmelo_Ponente, you have the right to question it and contact support… but i personally wouldn’t return mine for this, but i have seen people on this forum return it because of it…
Yesterday I backed up my AR2, loaded a new empty project, and then updated my machine (while crossing my fingers and lighting candles). It updated perfectly and everything seems to be working great. Whew!
mk 1: velocity mod functions as expected, numbers accurate but visual reference snaps to max.
New firmware!
https://www.elektron.se/wp-content/uploads/2020/09/Analog-Rytm_MKII_OS1.60A_readme.html