KC virus knob behaviour and os questions

[horsegrip]

G'day dudes.
I've had my KC for over a decade and served me well. But now I've ran into a couple of issues.
1/ I'm not getting data changes on knob behaviours or buttons. But it's not the buttons or knobs as the work in certain situations as documented in the video provided.
I'm maybe wanting to reload the firmware, but my os is 6.6 and the only firmware at Access website is 5.5. Where/what happened to that firmware and should I downgrade?
2/ For unknown reasons, I have lost a lot of saved patches on A-B bank. I've never performed any sys ex bank/patch dumps or the like. An never been prompted to replace the battery. Any likely ideas?

https://youtu.be/sNQ42F_u1ac