Cadence varies wildly and is inaccurate

It seems since the last PC/Window app update that my cadence varies wildly and is inaccurate.

I use a Bontrager Duotrap for cadence and a smart Saris wheel-on trainer. Zwift is running Ant+ to a dedicated Dell gaming laptop. I checked the cadence being displayed in Zwift against my dedicated handlebar mounted unit and the handlebar unit was accurate and Zwift readings were all over the map.

If I stop pedaling the rpm drops to 0. When I start back pedaling the rpm immediately jumps way high - like over 120 - then slowly works its way back down to a number that is not always accurate. 10-20 rpm increases/decreases are often not reflected at all.