[Schottlandru]

Thanks, yeah... I've tried a few things.
Latest was updating video drivers.
I would love to hear if any of you can re-create the issue:

In a session with lots of clips, if you display volume lanes on all tracks, does that slow down your scrolling, zooming etc?
Same with track heigh -> smaller tracks, more lag? Large tracks (4-5 or so on screen), smoother scroll up/down?

Also, does the scrolling freeze the TC counter?

All this happens here... even an empty session with say 150 audio tracks, no plugins or audio, shows this behaviour.
Smallish dialogue editing sessions with volume automation lanes -> sluggish.