Confirmed...
As determined by engineering, it has turned out to be an electrical failure.
Interestingly, this occurrence is NOT so rare, as we had an almost identical incident a few years back (faulty gauge)
A theory could be; these digitally operated systems simply don't like wet/humid environments. Development then has the challenge of designing a system that can cope better in these conditions.
This has been another one of those interesting learning curves and hopefully this thread may help out the next guy/girl who experiences a similar occurrence.
Something else I'll take out of this; I think by drawing back on our training, sticking to the basics and maintaining a habit of flying any helicopter (analogue or digital) within it's limits, we have a pretty strong case to suspect something might be amiss, even if it might be VERY out of the ordinary. Then it comes down to troubleshooting.
Good old fashioned "Seat of the pants" vs "the computer"
Safe flying!