Pedal signal jitters / oscillates in PurrOS

Worked example from a real ticket: brake values oscillating wildly on the customer’s PC but rock-solid on three of ours. Diagnosis path:

1. Plug into a USB 2.0 motherboard port, no hubs.
2. Lower max brake force and compare — helps distinguish signal noise from hand/foot tremble at the top end.
3. Suspect EMI: wheelbase power bricks (e.g. Simucube) within ~20 cm, LED strips on the same circuit, nearby AC compressors or transformers. Power the rig through an interference filter, unplug accessories one by one, and ground the rig + PC.
4. Try a different PC/laptop to rule out the environment.

The pedals carry strong EMI protection (certified with no sensor influence), and main electronics live in the brake pedal — the Molex link only affects the throttle. In the ticket case the electronics were swapped as a courtesy and the residual noise was traced to the building’s environment (transformer ~15 m away). Verdict from the customer: “stellar support… inspiring.”