Anyone else experienced this? Even better, does anyone have a fix?

My Saint rear derailleur’s clutch has been switching itself to the off position while riding lately. I can’t identify what situation causes it (rough vs smooth trail, pedalling vs freewheeling, etc) but sometimes it’s be fine for a full descent and sometimes I reset it and it switches back off pretty quickly. Chainslap noise is a pretty noticeable sign that it’s switch itself off and is the main reason I want to fix it.

I moved it onto my new bike about a month ago, before which I gave it all a clean and tightened the clutch tension a little. So I guess reducing the clutch tension would be something to try, but I would have thought that more clutch tension would keep the lever in the on position a little better.

Any help folks?