Today on the Innsbruck ride, my RPM was totally erratic.
It would not show on the screen but it would indicate a very low RPM on my iPhone, despite my Watt/kg and my BPM being comparable under the same conditions.
My Tacx Neo Smart was fully paired, no problem there.
My climbing speed would be negatively affected and so was my KOM timing.
My avatar would keep standing up with the low speed which is usually never the case.
To top it all, Strava did not have any RPM statistics to show for my ride.
Using a smart trainer like your Tacx Neo, your Zwift speed should be based only on the power reported by the Neo to Zwift. The erratic cadence readings would have no effect on speed in game.
To research the cadence reading problem, I’d look at replacing the battery in the cadence sensor, and ensuring that the sensor and the device you’re running Zwift on (iPhone?) are close enough to each other.
My understanding is that the Tacx Neo Smart takes control of everything, including the cadence. In fact, the battery in my Giant Ridesense has been removed because it was conflicting with my Shimano FC-R9100-P Power meter. I do not leave my Garmin 1000 on the bike when Zwifting therefore no conflict there neither.
The fact that a (low) cadence appears on my iPhone but no cadence indicated on the main Zwift screen is also odd.
Today was the first time ever that such cadence issue happened to me.
One precision: I run Zwift on my opened laptop linked to a 55 inches screen, with my Companion Zwift opened on my iPhone. All in all, there are 3 viewings: 2 duplicates (laptop and screen) and my iPhone. Everything is all pretty close to each other.
I haven’t been able to pair my power meter. However, Monday, the cadence was back to normal on the Richmond ride. And to this day, I had no problem. I can’t wait to hit Innsbruck again, just to see how things will go…
