ok.. my theory is, that, because it was such a humid morning, with lots of fog in the morning, and commencement of rain in the afternoon, each time the MMM thermally cycled from cold to hot to cold, small amounts of moisture condensed into water, which eventually found some small crack or break in the PCB protective coating and got into the electronics..

And FYI mr Shaun, I do use full throttle, and at least I'm not the slowest steerer at the track