Have you tried activating OpenGL:
PS: It would be nice, if Dreamtonics would support Metal instead, because Apple won’t support OpenGL for much longer, as far as I know. But currently it should still work even on Apple Silicon.
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So, today I’ve spent about 2 hours on the phone with Apple support, neither the OS SONOMA nor Logic have issues on my machine, so it must be plugins side (wich one I’ll investigate in detail) and presumably the m-audio device that causes all the lag and stuttering. We’ve done a lot of experiments with the Apple guy.
My thoughts remain that the OS and Logic are written to fit together. 
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Ah good point… I was looking for it in the macOS settings 
Yes! That solves 99% the issue, meaning that there is still a little playhead shaking – say less than one-second long – at each view change of the piano roll during playback. Thanks for the great advice, @Aymara !
However, it works only for the standalone program. The VST still suffers from the issue, even with OpenGL selected – tested it in Cubase Pro version 13.0.20.
Time to contact Dreamtonics support
Is it only a graphical issue or is the audio also laggy?
As far as the Dreamtonics Support is concerned, I contacted them two days ago and they responded. That’s why I uploaded a video example (link a few posts above) that they asked for. Audio has no issue, as you can also hear in the video.
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Well, that’s the important thing
And regarding the graphics issue … well, Apple stopped OpenGL support in 2018. It still works, but it’s deprecated, because Apple stopped OpenGL development for macOS (& iOS) in favor of Metal since macOS Mojave in 2018, as far as I know. And that might be the route to go for Dreamtonics, as for game developers too or all other software developers, who depend on graphics performance.
Then there’ll be loads of work for Dreamtonics guys to do in order to switch from OpenGL to Metal 
Apple forces third party developers nearly every year to update their code to be compatible again with their changes to macOS, e.g. new security features.
My Native Instruments stuff for example often needs more than half a year to be fully compatible again.
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I started a new Logic/Synth V project yesterday and it behaves exactly like in your video. Tested using OpenGL but that only made things worse. I’m on Sonoma 14.3 and use a 2019 27" iMac. 3,6 GHz 8-Core Intel Core i9, 64GB RAM and Radeon Pro Vega 48 8 GB. And Synth V beta2.
However, no audio problems and no crashes so it sort of works.
Hope they release a new beta soon!
Four days ago, the Dreamtonics Support emailed me that they have forwarded the issue to their dev team for consideration. Let’s hope they find a fix.
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Thanks but it doesn’t sound very reassuring! I better contact support as well so they understand that this is a real and annoying issue for many users!
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Everybody being affected should contact support. The problem is, that OpenGL is no longer supported by Apple and switching to metal … I fear … is a lot of development effort.
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Yes! Absolutely! And I have sent a detailed report about an hour ago! Hoping for a new beta soon!
I doubt, that the next Beta will solve that problem, when I see how huge the dev effort is to migrate OpenGL to Metal. THIS article might give a slight overview, how much documentation a developer has to check to learn it.
Something is off with Synth V and Mac OS Sonoma and perhaps with Logic? It is almost impossible at the moment to play anything live in Synth V, unlike sometime ago. I noticed that the screen behaviour changes after a little while. In my case the top of the screen that shows the stems has bars 1 -13 visible, while the bottom screen that shows the pitches has, say bars from 1- 6 visible. When starting the cursor is at least 1/4 note behind. The main problem however is that the notes have crazy latency and just can’t be played in rhythm and also miss any faster notes. After the top screen has to refresh and show the next set of bars (from 13 - 23) the cursor moves normally and you can play the notes in time without latency. So it’s something to do with the beginning and then it seems to sort itself out? Will write about this to Dreamtonics also. I’m using the latest released version of Synth V, so no beta at use.
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This is both interesting and disappointing. I thought that the problems only occurred in the most recent beta version and latest Sonoma. Please report to Dreamtonics support asap! They really need to hear this!
I have wrote about this to Dreamtonics. I had no troubles in Mac OS Sonoma 14.2 so it appears something has changed with Mac OS Sonoma 14.3. I tested this more last night and it is a very strange problem as it worked on some occasions and not on some other occasions 
but I could not work out what was the cause. At one point just changing the order of the tracks in Logic Pro seemed to work but when I continued working, the problem re-appeared.
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