In fairness, Wahoo have got back to me pretty sharpish, suggested all the usual reboots etc. There is a chance all is broadly resolved, although there is a suggestion by Wahoo that there could be an optical sensor issue. Without any doubt, a wattage floor kicks in, especially in the big ring, at about 90 watts, in the little ring this is at about 70 watts. I’m not the main user and haven’t encountered a floor before, although the original issue was drop-outs and not a wattage floor. Fingers crossed this was a temporary issue and I’m hoping might be sorted. On a better note, as yet my Core hasn’t missed a beat!