When I first upgraded to Dorico 4, projects that sounded great on version 3.5, sounded glitchy. It was totally unusable. I am on a Windows 10 PC, with a Focusrite Clarett 2 pre USB sound device.
I was running at 44.1K.
For grins, I tried 48K (no joy) and 96K eliminated the glitching and now everything sounds fine.