I solved the problem, the issue is hardware-related.
Unlike other applications, Zwift quickly increases and decreases resistance when enabling ERG mode to set the starting level to zero. In my case, resistance control has issues, especially during quick retraction. If the resistance changes gradually (over an extended period), the screw actuator works correctly. However, if the change happens quickly, particularly during retraction (reducing resistance), the screw can stop, causing cracking noises at the connection with the motor.
The problem: I can’t insert a link - YT private film watch?v=MDLK2ksAVog
Solution: (I can’t insert a link - search for an article) 7066894670108-Cleaning-the-motor-screw-thread
Now also in zwift the resistance when starting ERG works correctly