Trainer dropping out?

I occasionally do my Xert workouts in Zwift- my iPhone runs the Xert app loaded with the day’s workout, and is configured for trainer control. I then punch up some route badge I still need in Zwift, making sure I disable trainer control. For the most part it works very well, however once every few minutes I will notice a slight resistance change from the trainer, even though the Xert app calls for a steady wattage. Does this suggest I may be experiencing dropouts of some sort?

Do you also have a power meter on the bike? It could be power match if so.

I do, but I don’t use it. Kickr connects via BT to phone (running Xert) and ANT tp PC running Zwift.

For all types of workouts and every time?
I will notice slight variations on SMART intervals of fixed duration but it’s random depending on my cadence and target watts.

I’ve had a similar experience today using the android app. I use my Wahoo Bolt to set the resistance on the trainer and turned the trainer off in the app , or I thought I had on the workout screen, yet when the workout finished the resistance really dropped out so the app must’ve been having some effect on the trainer. I’m going to remove the trainer from the app and just use my power meter.

Try running without Zwift altogether and see if these still happen. Zwift autoconnects to the trainer even after you remove it from the list. If the resistance is set on the trainer, a dropout wouldn’t affect it generally. Usually something is sending some other trainer control sequence to it if you feel it.