Funny resistance Wahoo kickr

Sorry if this has been addressed before.

The other day I had to quit a race due to a tech issue I had not experienced before. The resistance on my trainer started going haywire. Hard-easy-hard-easy. Then it progressively ramped up to where I had to stop, I literally couldn’t not turn the cranks. I’ve done a bunch of races and rides and this has never happened before. My warmup before the race was fine, then this stared happening a little bit in the pen. It subsided and then really ramped up about 5km into the race. When I came to a stop I checked the pairing screen and everything appeared to be in order

Setup:
Zwift on Macbook pro (catalina)
Wahoo Kick (2017) paired via ANT+ (controllable trainer)
Favero Power Pedals paired via Bluetooth (power source)

This has been my setup for many, many rides.

Many thanks.