Random massive increase in resistance during workout

I’ve been trying to track down a new bug I’m hitting. I’ve been using Zwift with a Wahoo Kickr (zwift running on my Mac laptop) for a few years, without this issue. Starting this year, during a workout, the resistance will fluctuate randomly, and massively, to the point where I can’t turn the cranks…and thus can’t continue the workout.
All software and firmware is up to date. I tried hard reset the Kickr and then resync and recalibrate. I didn’t have the issue for 2 rides after that, and now it’s back. So I don’t know if that did anything or not.
Anybody having similar issues? It’s very frustrating and will cause me to cancel Zwift and return Kickr if I can’t fix it.
…One more thing to add: I rode ~25 min today / 11 miles in the workout without incident, and then it kicked it. So it’s hard to reproduce immediately.

Are you doing any preconfigured programs? I have found on their custom workouts, you have to gear down to a mid gear or the resistance gets all whacked

Hi. Same here and I’m using a wattbike atom. Can’t get to the bottom of it and it’s now also just fluctuating multiple times even on the flat. I’m already using my wattbike app more than Zwift as it makes it virtually un rideable. I only use zwift routes and workouts.

I had the same problem when i first began using my Wahoo Kickr, i believe i traced it down to the fact that i was using Zwift companion and the Zwift desktop at the same time. I do not know for certain, but since this happened a few times i have stopped using the companion app while riding and never experienced the problem since.

As an FYI running the companion app on the Samsung Galaxy S8

Thanks James. I’m only using via an iPad, without the companion app. I have used it with the app open on my phone before, but only once. Wonder if that threw it out of whack?