Power value is not costant

Many thanks for sharing!!!

As you are using both units, do you experience actual resistance fluctuations also more in the Tacx rather than the Kickr?
I don't want to influence your thinking, but at least I think I experience that the Tacx indeed drops resistance sometimes without a significant change in my peddling force/cadance, so initiating the change in resistance rather than reacting to my efforts.

The reason that I am asking is that with the Tacx software update things changed. And Garmin/Tacx proactively recalled my unit. But the new unit (higher serialno) shows the same behavior as my old after the software update.

A.o. it could be that
(1) before the update the data was flattered, and with the update more realistic data is reported.
(2) with the update the trainer has become more sensitive to changes in peddling (force applied/cadance) leading to the Tacx trying to compensate resulting in the very jumpy resistance.
(3)  the steering of the resistance has issues (initiating resistance fluctuations rather than reacting to the peddling in ERG mode)

I focused lately more on enjoying training than sorting this out (both ERG-type and virtual rides, which is to be honest not really hindered by this issue). Nevertheless your post triggered me to follow up my plan to collect 4iiii power meter data alongside the power data of the Tacx.

I am hoping that others are willing to share also their data e.g. from friends using other smart trainers then the Tacx's. E.g. a friend of mine has an Elite which also show the power fluctuating a lot.

Hello,

i also thought about the flattering, but i put focus on a steady ride and there are really drops in the resistance. My boyfriend tried it either and he confirmed my experience. 

I already contacted Zwift and they reported to have several inquiries with the same problems with the tacx flux smart 2

I have only used my trainer with the Tacx app so far. The data looks fine to me compared to rides I have on a Wattbike.

When you posted your before / after pictures some months ago, the 'after' picture looks correct to me.

I've not had any issues with resistance changing unexpectedly but I have only had the trainer for a week.

ive come from an original kickr to this and the trainer cant maintain the effort.  i have swap tonthe big ring to get the correct power values on the screen.  the power meter onnthe bike is showing 10-15 watts  higher.

it doesnt help if use the powermatch on trainer road either :-(

Same issue here. Using Bluetooth and the Windows desktop app. It doesn't seem to be a connectivity issue (readings on my Edge530 and desktop app correlate fine). I'll get random decreases in power levels (feels like freewheeling) or random increases (constant power level then sudden increase in effort). Also had issues with intervals where I would ramp up the effort to the target value then the Tacx would suddenly drop resistance and I'd have to shift all the way down to my 53x11 and pedal at 120rpm to even get close to the target value. Initiated an RMA but am not hopeful a replacement unit will fix the issue.

I have the same problem. Started directly after the firmware update. So must be a software bug.

Same here. Everything was fine until a couple weeks ago. Random power changes. I'm on 3.3.4/1.1.6. I noticed in the release notes they say improved "power stability and power accuracy". lol.
this firmware has been out for a long time, so I'm not sure what else changed on my end. 
https://forums.garmin.com/sports-fitness/indoor-training/f/tacx-flux-s/221313/tacx-flux-firmware-3-3-40-1-1-6

forums.garmin.com/.../1187436

Noticed my replacement unit has .45 software. Much better stability during the past two interval rides. Hopefully it stays that way!

Same problem,  I wrote to Tacx on line support, one month ago, the answer was thst my complain has been added to a ticket, but im still waiting..  For shure nothing goung to happen and if you want train with constant numbers on erg mode, this device doesnt work. Really disapointed with my election..