DCTL list shows NONE, sometimes wrong one

when I'm using DCTL, the list sometimes would show NONE, I can't see what's using in it, but when I press spacebar to play, it shows up the real DCTL I'm using, I've tried left and right bottom, not working, just the spacebar works.
this exist from resolve 19-20 beta 2, still not improved. I'm using fixed node tree, some bigger projects would have this kind of issue.