Mercury Transmit - poor quality / pixelated output

I have recently noticed that the quality of the Mercury Transmit preview in After Effects has taken a hit - edges are noticably pixelated, as if it were a half resolution image being blown up. This has not been a problem before, I've only started noticing it after coming back to work after the Christmas break. I'm on the latest After Effects (22.1.1) on a Windows 10 system with GTX 3060 graphics (latest Studio drivers). To help troubleshoot, I've opened the same project in AE 2021 and everything is fine/ as expected, so I am minded to suspect a possible bug in AE2022 as opposed to my system or set-up. That said, I don't see anything in the known bugs list or indeed other forum posts with similar issues. Anyone else experiencing this? Any thoughts / suggestions gratefully accepted. Thanks!