Tacx Flux 2 to Zwift - Disconnecting/losing signal mid ride/race


I purchased a Tacx Flux 2 and purchased a Zwift subscription about 2 weeks ago. I am connecting to Zwift using the latest MacBook Air via Bluetooth. The Tacx Flux 2 connected just fine initially, and I completed my first ride with no issues.

On my second ride, midway through it randomly lost signal. The ERG mode was disabled, and cranking the pedals resulted in no wattage being read. I attempted to disable ERG mode, unplug and plug the trainer back in, force quit the Zwift app, restart my computer and every combination of these steps multiple times. I had to throw in the towel and quit the ride.

The next morning, the trainer hooked up without a beat and I was able to complete a ride. I rode again without issues, but the following ride it happened again. I am now 6 or 7 rides in and have had this interruption 4 of the times. It seems to happen around the 2 hour mark.

There are no other bluetooth items interfering as I have read online. I disconnect everything in the house to keep it exclusive between the MacBook and Tacx, but it doesn’t seem to help.

I am confident this is an issue between Zwift and the Tacx. The Tacx connects to the Tacx app on my phone no problem every time, and my HRM and powermeter on my bike connect to Zwift without hesitation.

I am hoping for some recommendations on how to solve this problem. It is very frustrating as this is my only option to get in my training currently.

Thank you for your help, have a great rest of your day!


Does the performance chart from your ride show these signal dropouts? Could you upload if it does?

Hi @Kyle_Jennett_6564

Welcome to the forum.

Can you upload your log file to zwiftalizer.com and look for the amount of dropouts.

It can be many things that interfere, like florescent lights, microwave ovens, bluetooth headphones or even WiFi signals.

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I have a Tacx Flux 2 and am using a MacBook and have exactly this problem too.

It always connects fine, and then some rides (maybe every 2nd or 3rd ride) it will cut out and some point along the ride. If it turn the trainer on and off it will eventually reconnect.

I’ve uninstalled the app from the MacBook and its still the same. So frustrating.

I have the same issue with a Tacx Flux 2. Sometimes it dops the connection. Sometimes the ERG gets dropped. Sometimes the trainer won´t adjust the watts to match the workout.

Garmin says that they are working on a software update.

Zwift team, can you shed any light on the matter?

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I have the same issue - it doesn’t seem to matter whether I connect via ANT+ or BT and is very inconsistent and intermittent. Yesterday I had to disconnect and unpair everything and re-do it all. Then for the past 3 rides, I lose signal when there are big shifts in wattage for the program I’m following on the day.

Is this a TACX problem or something to do with Zwift specifically?

I spent some time getting my tech troubleshooting on yesterday and here’s what I found:

  • Windows Update (although it was only a security update) and rebooted the PC
  • Downloaded and installed the TACX iPhone app and updated the trainer to current firmware
  • Disconnected all paired devices from the Zwift Windows app and rebooted again
  • While the PC was rebooting, I did a calibration from the TACX iPhone app and checked all the trainer settings
  • Once I restarted Zwift, I re-paired everything and did a calibration on Zwift

I did my Threshold Development ride all that and no issues. Holding thumbs it remains that way!

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Hi, I also have a tacx flux 2 and use it with a MacBook Pro via Bluetooth and have recently had the same problem- really frustrating mid races or meet up rides. I’ve done the same-trainer Firmware update, Zwift latest update, not using any other devices anywhere near it. None of these worked but last one I’m trying is latest update for my MacBook Pro. Will see if it works. If not, I’m not sure what else to try. Anyone else found a solution?

I’m having the same issue here… I have the TACX Flow Smart trainer. I’ve checked for any updates, turning off my phone’s bluetooth so my trainers can connect with my laptop, unpair and pair, disconnect my trainer and connect it back again… And non of this has worked. Yesterday I ordered an ANT+ USB to see if that solves the problem, but I’m really frustrated about this situation.

Could you give us some feedback regarding this issue please?

Hello from Chile.
I bought the tacx flux 2 smart trainer and I’m “happy” to see that this is not a problem with my device but a general problem.
Effectively I have all the symptoms you describe in the post. Really really frustrating, especially when you are in a race or in a meetup.
I don’t know if any update is the reason, because I felt its happening in the last…45 days.
I’m using zwift in a windows 10 OS, and in an android mobile OS and it had happened in both, but the connection with my garmin on the bike is stable.
I haven’t been using the tacx app as often to say that I doesn’t happen there but seems it does so far, I calibrate the trainer often there to eliminate that risk.
Sometimes the erg mode keeps disabled in a reconnection (1 time), Campaignon never came back (1 time) and reconnection couldn’t be possible(2 times). In 3 months the amount of incidents were 4 in PC and 2 in android.

Sometimes if trainers get hot they lose connection. You could try pointing a fan at the trainer.

I did actually

I use a Tacx Smart in combination with a Mac Book Air which is a bit older and use the Zwift Companion app and a Garmin Edge 1000.
The plug for the Tacx is very loose and drops regularly. I had to tie with a piece of rope (obviously not a Zwift problem).
Otherwise the combination works fine except that the power measuring is a bit off. I am doing the FTP Builder program and I notice that at low wattage, f.e. 125 W, my wattage is far too high with an rpm around 90, which is recommended. At higher wattage I can’t seem to reach the recommended power level whatever I do. Shifting gears helps a bit but shouldn’t be necessary as the program works in ERG mode.
I see the same on my Garmin, which is much more stable anyhow than Zwift, where the power fluctuates hugely, especially at lower wattage.
It could be the Tacx, or the connection (I use BT and ANT+ separated from the laptop).

Does anyone recognize this problem?

Thanks a lot for your answer


This is clearly a problem between Tacx and Zwift. Could someone from Zwift acknowledge the issue and offer solutions please? Doesn’t happen with Sufferfest app or the Tacx app - only Zwift.

Having invested significant time in trying to resolve this, I am almost at the point of giving up and moving to a different ride app, which would be a shame.


Same problem here. Tacx flux 2 and losing power for few seconds at the time. I noticed that it’s usually happening on long ride (last time it was Le Etape, after aprox 1h45min into ride), and when i tried to put more power. It was okish when going steady 1,5wkg, higher the power more likely it was to have a signal drop.
And never had problem before Zwift updates (last 2 bigger ones) even when doing 3h+ rides.

As Ben said, I feel like it might have something to do with overheating

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Looks like I’ve joined the club. I’ve been using my Tacx Vortex on Zwift for three years without a problem. Yesterday the ERG mode failed mid ride. I tried restarting Zwift, and now it won’t even pair with my trainer, so I can’t ride at all. To help troubleshoot, I checked the Tacx Utility app and the trainer software is up to date, and the trainer connects to my ipad via bluetooth without any problems. I’ve uninstalled and reinstalled the Zwift app on my ipad and my Macbook (which uses an Ant+ dongle), and the problem still persists on both platforms. Is anyone from Zwift reading these forums and offering ideas???

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Regarding dropouts with the Tacx Flux 2 I can recommend watching the video or reading the article from DC Rainmaker.

He recently did a review for the Tacx Flux 2 on his Youtube channel / Blog

I’m on a Tacx Flow and notice that when my flow drops out, that it is still “paired” with the zwift app (using an AppleTV). I thought maybe my wifi was weak and zwift wasn’t getting the bandwidth it needed (even tried a range booster since I’m in the garage), but the zwift appears to be working just fine and it is showing connectivity. The bluetooth from the trainer even seems to be working, since it’s showing that it’s connected on the app, but I did notice that green light on the trainer is turning to red. The power drops off, and all data on the zwift app goes down (power, cadence, ERG of course).

I will try the fan idea (already have a fan blowing on me). Almost wish there was a hardwire option to my appleTV or something… I will double check updates, but think I may need to reach out to Tacx.

I have been using a tacx s flux for months with no problems until the last week i am having constant dropouts now

I don’t think this is limited to the Tacx Flux, my Cycleops H2 does the same.
Tonight, @50 minutes in to a workout, and it dropped out. Seems to have been getting worse over the last couple of weeks. I just pause the workout, go to pairing screen (still shown as paired but cadence says no signal and turbo itself shows searching for connection), disconnect / reconnect and go back and resume the ride.
Absolute pain in the backside though. So it could be that it’s not necessarily a problem with the trainers and might be more to do with Zwift.
Just for the record my set up is:

Cycleops H2
Huawei M6 mediapad
Xiaomi note something or other (companion)
Wahoo Tickr 2 HRM
Garmin 945