Some pointers I got from Zwift Customer Experience Agent which you may find relevant:
Some users have tried these steps and claim it works (but they have to do it each time):
- Unpair your smart trainer from the Paired Devices Screen (Power Source, Controllable, Cadence)
- Power off (unplug) smart trainer.
- Leave unplugged for 2 minutes.
- Then turn it back on.
- Pair your smart trainer to Zwift under Power Source, Controllable, and/or Cadence.
- Continue your ride and see if resistance re-engages.
If you’re continuing to have problems with ERG mode or resistance in SIM mode rides, put those steps into practice and please let me know if it helps.
- Also, have you tried turning off native (built-in) Bluetooth on your Mac and then pairing your trainer to Zwift using the Zwift Companion? If not, maybe give that a try and see if it helps. We’ve written a guide for connecting via BLE on our knowledge base?
- Alternatively, you can also use ANT+ as a means of pairing your Kickr to Zwift if you have an ANT+ Dongle and USB 2.0 Extension cord. Since this issue has been identified as being a problem primarily with Bluetooth pairings, you may want to consider trying ANT+ as an alternative pairing method.
- Check the Elite app for any firmware updates and if there are any available, please download and install the latest firmware.
Hope it helps!