Zwift Hub Flashing Red Light

Good idea, I hope you don’t have to wait too long. By the way I just got a reply from support and they are ignoring the issue with the flashing red light and pointed me to another pointless article on how to perform a spindown calibration even though automatic spindown calibration is one of the features of the new firmware lol I’m trying to be patient but it’s hard when they take so long to reply and when they do it’s with some useless stuff.

Good idea, although I was going to do that and make sure everything works before I return my existing one.

What concerns me is there doesn’t appear to be a method developed to rollback the firmware or even attempt a repair if it goes bad. Jetblack, at least, offers an article to use the nRF Toolbox (develop for the chips inside) and a link to the firmware to attempt a recovery. We seem to have a situation where if the update breaks it will require a replacement unit, to resolve.

Also, if there are ‘features’ in this build that would result in the firmware update being pulled, there is no back out plan to restore the previous one. Users would have to wait for another firmware update to be available.

Of course, not all users are technical and not all users care, so would struggle with the steps above but it does provide an avenue for users to explore and attempt themselves, rather than waiting on a new unit. Ideally the routine would be available in the companion app - restore previous firmware, attempt repair, etc!

1 Like

I agree, it doesn’t seem like a viable business plan to just replace units without even giving customers the chance to attempt a fix.
I’m really surprised they said they’d do this without even seeming to do any investigation.
As long as I get a new working unit I’ll be happy but they surely can’t sustain this if it’s happening to lots of units

I posted in the other thread that I’m having a similar issue since upgrading to v4.0.0. It won’t stay connected to my PC anymore (says “No Signal”) but it connects fine to my iPhone. I can connect it to my work’s MacBook Pro and do a ride okay although I did notice that it occasionally flashes purple. I uploaded my log file to zwiftalyzer, but it doesn’t show any bluetooth dropouts or trainer resets.

I guess I’ll file a support ticket, but based on the comments here, it doesn’t seem very promising. I think it’s clear that v4 introduced some issues.

I am having the same issues with my Hub, it has worked flawlessly up until the V4.0.0 firmware update. My Hub is having issues with connection to the game. It is blinking blue then purple. Initially my laptop wasn’t recognizing the Hub at all. Unplugged the Hub and restarted my laptop and was able to get it paired, then after a while i got a disconnected notification mid group ride and could not get it reconnected. Any answer from support what may be going on?

I finally got a resolution from Zwift support. Same as Chris above, they will be replacing my unit. They said it will be brand new, but that I may need to update the firmware once I get it so I don’t know… but kudos to Zwift for stepping up and making things right. I have to return the old unit within 14 days after I get the new one, they sent a return label for that. They’re also saying that at this point there is no way to revert to a previous firmware so I guess that’s why they’re stuck replacing them but I don’t know how true that is since according to another post Jetblack is doing it with the Volt which is what the Hub is based on.

Dale I would contact support just tell them that your Hub got bricked with the new firmware. They’ll send you a bunch of unhelpful articles the first couple emails but eventually they’ll tell you they’ll send you a new unit. Hang in there!

I too have the deadly red flashing light. The only thing that doesn’t seem to be working is that I can’t connect the hub to my phone anymore - so presumably would never be able to update the firmware again. I’m contacting support as my next job.

It is an odd fault, mind connects to my phone ok and says firmware up-to-date, and still connects to my pc and works (so I can ride) but the power feels off (possibly the auto-calibration feature?)
I’ve been sent a new unit, which should arrive in the next couple of days, and been told I have 10 days to test it before returning my existing one.
Plod through the support process and you’ll hopefully be sent a new one too.

1 Like

Thanks David, I haven’t dove into it to much. Initially i wasn’t able to pair aything to my laptop. I was just stuck on the pairing devices screen, with the hub flashing blue then purplish/Red. So started trouble shooting. Unplugged the Hub and plugged back in with the same result. Then escaped from the Zwift app and restarted still the same result. Started to get a little frustrated. Next i restarted my laptop as i usually just put the laptop in sleep mode because i only use it for Zwift. That seemed to work. I was able to pair all devices and got in 2 hours of riding. Then I got a connection disconnected. Zwift was still working on screen but all devices, power, cadence and heart rate went blank. Tonight i am going to go through the standard protocol of uninstalling and reinstalling everything and go from there. Fortunately the weather is looking decent in my area or the next 3 days. Beyond that i may get a little irritated if i can’t use the Hub.


went to do a ride yesterday and the hub is stuck with a slowly blinking red light - it is not showing up either on the Zwift game ( PC w11) or on the ZC on my phone ( which says unreachable) - I have tested various Bluetooth options and there is no signal from the hub. It has been working OK up to this point ( only had a couple of weeks). I was not in the middle of a firmware update ( at least to my knowledge) and have tried turning off an don again - noting. I have opened up a case with support and am waiting but they refused to tell me if this was a common issue. Really frustrating - I fear will need replacing but hope this can be done quickly - anyone else have the same issue?

I’ve had 5 emails from various members of Zwift support. They assure me that the my problematic Zwift Hub has been referred to their superiors and the relevant departments. So far no solution has arrived. My red light is flashing quickly and will not connect to the Companion App, so future firmware updates will not be possible. I can ride the bike in game but I’m not sure about how accurate the power is. Yesterday Maria bot dropped me while I was putting out 4 Watts per kg - yet I was able to follow her today for 40km. Something is not feeling right.

So, following on from a few emails to Zwift support I have been sent a replacement unit.
I set it up and checked everything out. Seems a bit more dodgy connecting via Bluetooth, but it does work.
It came with Firmware version 3.8 and told me an update was available. I did the update, with some trepidation, and it succeed. The blue light is solid and the companion app tells me the firmware is up to date. Test rides work, I’ll give it a proper ride after work this evening.
The odd thing is the companion app is saying the firmware version is 3.9. Have they pulled version 4.0? It was the upgrade from 3.9 to 4.0 that broke my original unit and seems to have caused trouble for others, so I think if you’re having issues and they started when you tried to upgrade to 4.0, keep going with emails to support, tell them it’s version 4.0 that broke your unit and they’ll, hopefully, send you a new one eventually.

1 Like

My new one is in transit too. Well done Zwift!
I asked about whether the latest firmware would be pre installed. They said I would have to update myself but they would be there to help. That’s very interesting about v3.9 appearing to be the latest version as I would be nervous about updating to v4.0 again.

Thanks for the update Chris, that’s good news. I’m still waiting for my replacement to arrive but it should be here sometime today. First thing will be to update the firmware and see what happens. I wonder though, if v4.0 has indeed been pulled, could something similar happen with a future update? I hope they get that figured out.

1 Like

Good luck Tony we’re on the same boat, I’m nervous, I hope it doesn’t get bricked again. I’ll keep you posted.

1 Like

Got the new Hub and installed the update. Yep, got 3.9. All working ok now.

Hey all - our engineers have been investigating why some of the returned units did not take the v4.0 firmware update as expected. Thanks for flagging it up to us quickly so we can get to the bottom of things.

I’m crossposting this information to this thread to highlight a few details before updating, and some things to be aware of should an update fail.

Before updating firmware

  1. Verify you’re using the latest version of Zwift Companion. Please check our Latest Version thread , and confirm build numbers on the Google Play Store / Apple App Store
  2. Keep the phone within line of sight of the Hub trainer.
  3. Do NOT let the phone sleep. Be sure your phone is charged fully, or plugged in to AC power.

If you attempt a firmware update and it fails:

  1. Force-close the Companion app and re-open. Rebooting the phone would ensure a clean restart.
  2. Do not press the Forget button in the Companion app.
  3. Do not uninstall and reinstall the Companion app.

If several attempts fail, contact us for next steps.

1 Like

Just got the same problem yesterday. The red flashes every 5 seconds, it looks like solid red but every 5 seconds it flashes for 1 sec.
Tried with support but they told me they forwarded the case to more appropriate team.
The hub worked great the day before but the day after it just froze and this keeps happening no matter what I do.
Phone or PC wont connect it seems like BT is not working.

This is becoming frustrating since I just started recovery from my broken rib injury and thought Zwift could be a reliable training platform.