Low resistance in just ride mode on new Kickr Core

I bought a Wahoo Kickr Core a couple of weeks ago to replace my Tacx Flux which is getting on a bit.

I’m using an iPad Air 2 for Zwift over Bluetooth. I have latest Firmware installed on the Kickr and latest Zwift update on the iPad.

When I do a workout in erg mode it all works perfectly with Zwift and trainer controlling resistance and power as needed.

When in just ride the power I’m putting out is completely different to the Tacx for the same gear.

So 34-23 on Tacx is approx 100W on Kickr will start around that level then gradually fall to about 45W then settle there.

If I change up to 50-23 Tacx would give me 160-170W whereas Kickr is giving around 100W.

This also happens when running Zwift on my iPhone over Bluetooth and MacBook over Ant+.

This is on the flat, resistance increases as expected on gradients. Same resistance profile for same routes in same gear on all devices.

I have contacted Wahoo and Zwift support but not got to the bottom of it yet.

I have done spindowns and a factory spin down. I have also done a dropout test in Wahoo app - it’s not a power dropout.

Any ideas? Hopefully I have provided enough info.

I’m only guessing… Maybe check weight of rider in Wahoo Fitness App and Tacx Training.

Rider weight and height are fine.

Trainer resistance at 50% but increasing doesn’t make a difference on flat, only on hills

I am having exactly the same issue, Brought a Kickr Core a week ago and pretty much can not ride on flat due to spinning out of gears, which means no races because the power resistance is just not there to keep up.
Weight, height, correct, trainer resistance 100% (works on hills)
I have also tested this on Rouvy and fulgaz which is making me think it could be the trainer
I am in contact with Wahoo as well.
No trainers in stock to replace at the moment
Sorry no solution but feeling your pain.