Okay, while I'm on a roll with repairs (the pedals), I figured I'd see if anyone had a new "fix" for the mis-shifting Fanatec SQ 1.5. If you've not heard, they seem to go out of calibration in the H-shifter and then re-calibrating them, if it works, only holds for a short while. There are lots of "fixes" out there: tape to insulate the circuit boards, gluing the magnet, just opening and closing the shifter to clear static electricity, and putting ferrite cores on the data cable. New to me, however were comments about how the ribbon cables chafe and break or the connectors aren't tight. Apparently this is the real issue and the following video provided the answer for my shifter!
i opened mine to try diagnose it removed those as part of opening it and put them back after not finding a reason.. and of course its been working since then.. so yeah.