Dropouts and strange resistance behavior during Zwift Academy workouts

Hi there, I’ve been riding Zwift for over a year and have generally had a smooth experience, doing mostly races. My setup is a Kickr Snap, running Zwift on iPad 6th gen (latest Zwift 1.16.2), Android companion app and Airpod Pros connected to the companion app. I recently added the Bipr Samsung Galaxy BLE heart rate app for my Samsung Galaxy Watch 3. I’ve read other threads about possible recent resistance issues with iOS, but I’m not sure whether mine is related or not.

I did the Baseline ride in a group ride last week, all felt normal. Then I did the group Workout #2 and felt like I was spinning out the entire time - even at the 30 second 400+ watts sections, I was getting there with very little effort and spinning out. It was only on the very last set of intervals that I experienced what felt like more appropriate resistance. I asked others during the ride if anyone had experienced the same, everyone else was cooked.

So I performed a spindown on the Kickr Snap which also updated to the latest firmware and then yesterday I did the Workout #1 by myself. I assume whatever the default is for ERG was enabled, I did not change any settings. The behavior in this case was completely different where during the over/under sections the resistance was like molasses and I couldn’t get a decent cadence going. What’s worse is the moment I downshifted to try and speed up my cadence to something more reasonable, wattage according to Zwift would drop to zero and suddenly I’d feel no resistance at all on the trainer - I’d have to then shift back up and pedal for a few seconds so that Zwift would begin applying resistance again (at which point it’d be super heavy - cue vicious cycle).

As a result, my Workout #1 looks like the attached with all these power dropouts and the workout itself wasn’t as I’d hoped given that during the hard sections I’d frequently experience no resistance at all for periods.

Has anyone else experienced this or can help me diagnose? Thank you.

Not sure what bug happened when I was experiencing no resistance, but I re-did Workout #2 and this time experienced the same power dropouts as Workout #1. It happened to a friend of mine as well also using Kickr Snap so I can only conclude it’s either a bug or by design of the workout to turn off ERG if you drop slightly below the target power at any given point.

Setting power bias at 95% fixed this for me as it let me sustain the target watts and resistance stopped dropping out. This seems like a poor design feature to completely turn off all resistance if you’re struggling to keep up without giving you feedback as to why it’s happening, or it should simply drop your power bias for you if it senses you can’t keep up with the target watts.

Looking at your last workout it look like you still had a few power dropouts.

If you can’t match the target in ERG the trainer will add resistance to force you to up to that wattage, and tat will cause what we call the spiral of death.

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Looks more like signal interference than a bug, how do you connect the kickr to your device running Zwift?