Power Erratic readings +/- 100 on Kickr Snap

Hi all,

I’ve a wahoo Kickr snap, I have a cadence sensor and a heart monitor. I run Zwift on my phone and mirror it to the TV over Bluetooth.

I recently dug the Zwift out since the weather changed, it was like cycling through mud. I did a spin down after warming it for 10 mins and following the 2 turn rule - done via the wahoo app.

Then my power reading became erratic. They may have always been that way but I’ve learned more about cycling since I last used it so I’m only now noticing.

I did a factory reset via wahoo (hidden option).

That has not solved the problem. Can it be because I’m mirroring? Is there anything else I can do? Picture to show what I mean but my watt per kilo bounces from 1.8-3.8 within seconds.