Lost of my high pass filters simultaneously shot up to high levels (X3)

Well that was a weird one. I was working on a project last night and all of a sudden a lot of the tracks became tinny, some reduced to mere clicks. It turns out that on about 50% of the tracks in the project, the Quadcurve EQ's high pass filter was spontaneously set to high levels - all different but all over the 4000Hz level. I've had to go through all the tracks one by one and try and remember where it was set to. Not good! 
 
When it happened, I wasn't touching the mouse or the keyboard. In fact I was looping a section of the project and jamming with a synth on my MIDI keyboard. All of a sudden - bang. What on earth could have made something like that happen? I think I remember others talking about EQ settings being trashed months ago (heck maybe I was even one of them...vague memories!) but I can't seem to find the thread. 

I reckon that a lot of these new bugs are to do with the gui not updating properly or not being updated properly