Loud grinding on Zwift Hub with SRAM Rival Etap AXS with 12-speed

Bugs and Support
1

Hi together

I have a SRAM 12-speed etap AXS shifting unit. I tried to install it on a Zwift Hub and use the XDR adapter and a new cassette (the same I use on the bike SRAM XG1250 10-30). However, the “grinding” noise is really loud and does not sound “healthy” and seems to come from the chain (also I had the bottom bracket under suspicion). The bike is “quite” new and all parts have been used 800km. Guess, thus it should not be the chain. Unfortunately I cannot add a video/link to this post…

I already tried several steps:

  • installing bike several times
  • re-install new cassette on Zwift Hub
  • micro-adjustment of sram etap
  • tested installing Cassette with spacers (which shouldn’t be required as it is a 12-speed)

Nothing has so far been led to less noise… Hopefully someone has a solution. The last idea I have in mind is to install the cassette of my bike on the hub to see if that works.

2

It seems that the Zwift hub is not spinning the cassette smoothly but seems to have some “bumps”. In addition, I also installed the cassette of my bike. Whereas the sound was not as loud as the new one, the grinding is still present.

In addition I contacted the support team:

  • I wrote a mail (including video) to the support team and got a first response within 1-2h telling me that it looks/sounds like an issue of the unit and that me request is forwarded to the main support team. That really sounded promosing
  • main support team sent me a mail that the were not able to open the video link (which still works) so I recorded a new short precise video and sent it as an attachment 3 hours later
  • since then (3 days ago) no answer and no reaction from the main support team…

I am really disappointed as I want to start my indoor-training (weather-wise I do not want to bike outside) and seem to be blocked by a hardware issue…

Unfortunately it also seems to be hard to find another way to contact Zwift except via mail (support@zwift.com)

3

Also installed the cassette of my bike, whereas the sound in general was not as loud as with the new cassette it still was present.

Based on a new video I took it also seems that the Zwift hub is not spinning smooth and seems to slightly “wobble”

I also contacted the support team via mail:

  • first reaction from support team after 1 hour telling me that based on the video it seems to be an issue of the unit and request is forwarded to Zwift main support team
  • response from main support team 4h later: sorry we cannot open the video please send again
  • I sent a response including the video as attachment 4 hours later. Since then (3 days ago) I did not receive any message anymore.

Is there any contact possibility (phone/chat/etc) to speed-up the process?
I really would like to start my indoor training as whether-wise cycling outside is not an option.