Gapless playback stopped working

As the title says. What should I be looking at to troubleshoot?

Edit: I’m running Roon on Windows 10, streaming most of the time to a Cambridge CXN V2.

I’d recommend rebooting the affected devices.

No reason why either should not be gapless , CXN has always been gapless since V1

What is the music source , are the files gapless ? , I am not sure how they can’t be ?

Try Dark Side of the Moon on Tidal / Qobuz , THE test track for gapless