It was a ribbon cable inside the unit that was getting crushed slightly by the casing and adding pressure to the top connector creating the anomaly which I could replicate by pushing it ever so slightly. I managed to push the ribbon cable further between the circuit boards with a credit card and created a slightly larger notch in the plastic casing to give it more clearance. I reported this to Line 6 as this could easily happen again to someone else. It all depends how it’s hand assembled and this cable is folded as there’s little room for them not to fold it differently and the bends being slightly in the wrong place. The fault never reappeared. This had nothing to do with software or firmware at all. It’s a physical fault.