Thanks, yes with 125% scaling the FX interface is correct also on my system, but the text is much too small on my 27" UHD-monitor. It reminds me running Vp13 on an UHD-monitor - without application DPI setting.
Even with the MS recommended 150% the levels FX interface is unusable on my system
You could try 149% as a long shot - has been mentioned before as a possible solution.
I was a little bit lucky that others with 27" UHD monitors had mentioned this problem (before I purchased), so I went with the much larger monitors, and I must say the editing experience is very good with high DPI.