Cubase 8.5 dramatic FPS drop?

So this is strange, in Cubase 8.5 whenever the main project scroll bar/cursor is moving (the white/black line that scrolls as your project plays, whatever it’s called) I get insane amounts of slowdown. The FPS drop dramatically while the rest of Windows runs all the same. As soon as the scroll cursor moves offscreen everything gets back normal, my meters go back to full framerate and everything looks great.

I am on Windows 10, dual monitor setup at 2560x1440, Nvidia GTX 750ti.

Very important to note that Cubase 8.0.3 does NOT hava this issue.

By FPS I mean the window refresh rate. Everything around Cubase runs as it should, it’s just Cubase that gets very slow.

Update: This is only happening with Cubase 8 projects opened in 8.5. I created a completely impractically overloaded project in 8.5 and runs smoothly as it should (resaved that in 8 and then opened it back up in 8.5 just to test, still ran smoothly).

Update: So I loaded a project that was doing this, removed all the inserts effects and reset the channels, still slow. Then I removed all the instrument tracks and VSTis from the rack, still slow. Then I removed every audio/MIDI track (blank project), still slow. Then I removed the chord track, fixed.

So what is it about the chord track in Cubase 8.5 that makes it destroy the refresh rate?

So what is it about the chord track in Cubase 8.5 that makes it destroy the refresh rate?

never use it personally, but didn’t the chord track have some changes with 8.5?

Maybe another case of change one thing…break another.