Mixer Lag on Mojave

Hi all.

I just upgraded my system to Mojave from Mavericks. Actually I installed Mojave and Nuendo from scratch on a new NVME drive.

Right now audio performance is much better than it used to be on Mavericks and the system can handle pretty heavy projects it couldn’t without crashes or dropouts previously.

The big problem though is a major lag in the Mixer. Although the project window is fast and scrolling, zooming etc is fine, when I open the mixer, even in not so heavy projects (100-150 tracks, performance meter @ 40%-50%), the meters lag way too much, and scrolling is very slow. FPS drops to 8-12 when the mixer is open.
In heavy projects (performance meter @ 80%/90%, 350 loaded tracks), the project window and audio is again fine and better than Mavericks, but the mixer is totally unusable with massive lag.

It’s definitely not a hardware problem, as I get the same results with both a GTX 780 3GB (Nvidia) and RX 580 Pulse 8GB (AMD), both natively supported in Mojave. Also the cards run on their max clock as confirmed with istat menus so there is no throttling involved.

Any clues?

I tried the same projects on the Cubase 10 trial and got the same results.
Turning off Channel Overview & Meter Bridge helped a lot, but I shouldn’t have to do that