I recently went from using android Bluetooth with speed sensor only to android ant+ with speed sensor, cadence sensor and hrm. Since the switch my power in zwift appears to only be able to take on certain values, about 30w apart (see the attached pictures for the before and after power curve of two rides). The issue occurs regardless of the three second or instant power setting (with the three second setting it merely takes three seconds for each jump). Zwift seems to somehow use the nearest power within 30w to the one I’m doing.
Is this a known issue? I’m not sure if it has to do with using ant instead of Bluetooth or whether it’s to do with also using cadence or hrm.
I never got a response (either from Zwift support or my post on here), but I was experiencing the same issue using ANT+ on my android device that fully supports ANT+. The only solution I had was to get a bluetooth bridge (4iiii heart rate monitor) and use that with the Zwift app.
It’s clearly just an issue with Zwift on android and how well it supports ANT+ (I could use other apps reading the same data with no issues).
Interestingly enough, I just did a ride where I walked away from the trainer to hit the bathroom. The heart rate monitor (bluetooth bridge) seemed to stop receiving readings from my speed and cadence sensors. I switched both of those to ANT+ and it worked again (with the heart rate monitor still paired via bluetooth).
Either the ANT+ issues have gotten better as of a recent release, or the heart rate monitor still being paired via bluetooth changes how the ANT+ readings are received. There seemed to be a small delay vs bluetooth (and one drop out), but otherwise better than before.
Thanks for sharing your experience. Yes, it seems you are having a similar issue to mine. I used bluetooth initially but was only able to use one sensor at the time otherwise everything would drop out. In addition to the Zwift membership I had to obviously buy a trainer and sensors and then also the ant device, extension cable and usb-on-the-go adapter. I am not really willing to fork out more money yet again for countless workarounds of issues that are on Zwift’s side if I am paying £12.99 a month to get a proper service.
