Lane automation issue. Cubase Pro 8.0.20

In Pro 8.0.20 when I make adjustments to lane automation while playing audio using the mouse, the Cubase pro timeline will freeze for 5 to 10 seconds but the music keeps playing. It’s like Cubase is about crash but then recovers. There is no spike in the CPU meter while it freezes. When I stop the timeline I can edit the automation without issue. This does not happen in 7.5 running on the same high end machine.

I have disabled all 3rd party plugins to rule them out. I swapped my video card from GTX to AMD but same issue.