Thanks for your help guys. Previous firmware mentioned was just the 2nd most recent one that Line 6 Updater would allow me to select, 3.12 I think. And Mac OSX. I updated HX edit from 3.50 to 3.51 as well but I don't think this made a difference.
After messing around with it a load (a load of updates and factory resets etc) it's only happening now when the Kinky Boost is placed in the chain before selecting reverb. Then when you twist the big knob going through the reverb, each selection pops as you scroll. Are you guys getting that?
I think I might have an issue with the board, as there does seem to be other small glitches and it's just being quite untrustworthy. I noticed that when I was using my Poly-sustain, it keeps changing from Momentary to Latch without me touching the settings, and when I go into the settings, they still show Moment although it's not functioning in that way. Very strange and annoying as I'm using this live.
In the morning I'll try the disaster recovery, thank you for sending that over! Your help is appreciated!
I've tried to re-upload the video but it might not be working properly.