Unfortunatelly I have the same problem with 35 and 120 (nonCS) as reported here on l-camera-forum and it looks I´ll have to send lenses to Solms for repair 🙁
Video of the issue with S-120/2.5:
My lenses failed with old S2 FW (1.3.0.0) and older lens FW, after updating to last versions problem remains the same 🙁