I had to reinstall previous version!
Loop feature is now at best counter intuitive, or it may be faulty, I found I had to use the menu command to get it to work, simply selecting a region with Looping on did not work.
Then on loading an existing project with more tracks, I found that playback was glitching to the point of being unlistenable.
The change log for 3.1.1 suggests some of these issues have been fixed I will try it!
Steve