Zwift can't control Tacx Flux S

I am having a huge problem getting zwift to control my Tacx flux S. Its not controlled in either slope or erg mode. I have tried connecting both thru the companion app and directly through my apple tv.

The resistance changes l on/off every two seconds and it is the same for both erg and slope mode.

This is what it looked like when trying to climb the main climb on watopia:

My setup is as follows:

Apple tv 4k
iPhone 8 with companion app
Tacx Flux s

Any suggestions? The network connection is good, but can mini dropouts in network connection cause this? The router are two floors over the basement, but watching movies on the apple tv is not a problem.

Thanks in advance for any help,

Frank

One thing you might try is setting your wireless router to a fixed channel, instead of letting it (constantly) look for the ‘best’ channel. I had some issues when I first started using the ATV and came across a thread that suggested doing this. After I changed the settings to a fixed channel (pick one on either end, I think) I have not had any issues in over a year.

Thanks! Will try and report back.