Vector 3 L-R Balance wildly different on the road and on a smart trainer

My pedals are reporting around 66-34 split on the road and a 49-51 split on a trainer. The 66-34 is suspiciously like one pedal reading 50% low to the other pedal, which would result in a 33% split of the total power (if you see what I mean. ie: if one pedal is reading 100 and the other 50, giving a total power of 150, the percentage power of the pedals is 67-33%.

Has anyone else seen this bizarre behaviour which may be a problem of the right and left pedals communicating in the "real" world.

A fix would be appreciated.