Thought I’d supply a picture of a power graph from my last ride. It looks like there are two power meters with different readings that are alternating rapidly.
do you have anything else you could record the data on (a bike computer or watch) to see if the power coming out of the trainer is the problem or it is a problem with zwift receiving it
I’ve done some rides in the Tacx iOS app and there it works fine. But since the problem in Zwift isn’t always there and the Tacx app doesn’t use Sterzo or AppleTV it’s a bit hard to troubleshoot.
Anyway, I’m not a big fan of troubleshooting, I want to ride my bicycle. 
I’ll switch to some other training app and maybe return to Zwift next year and see if the problem is resolved.
Will be hard to solve your troubles in that case.
You have a point. But none the less, two weeks with nothing but trouble in Zwift is really annoying. I think I’ll go for Rouvy. And soon outside IRL is available.
I had the same problem & solved it by plugging my trainer (Kickr Core) directly into a wall outlet rather than into a power strip.