Tacx 3m issue with SYSTM

I just “upgraded” from tacx 2 to Tacx 3m. Unfortunately, the cadence is flaky while using the 3m. Same setup as before but having this trouble while using in erg. I bought an external cadence sensor and it works fine with SYSTM. I dont want to use an extra 40 dollar sensor on a 2000 dollar trainer set up. I have contacted garmin and wahoo.
Anyone else using Tacx 3m? with success?