ZML/ZCA (Android) - does its use increase dropouts?

I’ve had an issue of dropouts on/off for a while now. I’m on a Kickr, Win10/Zwift, ZML on Android S7, sensor on dongle next to Kickr, channel changes several times on router, etc. and all have the latest updates. It works about 90% of the time, but lately, it seems to be dropping out for 1-3 seconds every 5-10 minutes or so, which can be frustrating on group rides/races.

Yesterday while riding, I had to start my ride over mid-ride and in the process, lost the connection on ZML. For the sake of time/simplicity, I just turned it off altogether and just rode with w/o it the rest of the ride.

Well - guess what - no dropouts for the next 30 min. and the most consistent ride I’ve had for some months. Is ZML/ZCA the weak link in the system or is it something else related to the connection?

Try to turn your Bluetooth off on your phone. I assume you use ANT+ to connect to your Kickr.

Yes, will try that. When calibrating Kickr, it requires BT, so it often gets left on. I had it on, however, when the app was not engaged, and was working well, but it seems BT can also be a power hog and always looking for connections.


Thank you.

The last two rides haven’t improved much. I didn’t even use ZCA on the last one and was still getting multiple dropouts, and usually at the worst times. Everything else works well and my net connection is stable/strong and on the strongest channel w/ the dongle sitting right next to my Kickr.

What’s odd is the dropouts seem to come usually around a transition (from flat to climbing) or right at the beginning of a climb and often doing tempo up a climb where my avatar will slow, unclip and then start riding again. By this time everyone is up the road…anything else to try and it tends to ruin races when you’re going lights-out and then nothing.


So, I disconnected my trainer from Zwift and re-added all my other devices (cadence, HR, etc.). This time my trainer showed up twice, once showing as a FE-C device. I connected it and not a single drop-out…and it felt like a new bike. :slight_smile: Consider this solved!