@danny pan , good point - I just checked and can hear the slight hiss when I put my ear up against the frunk.
@P3dStealth , thanks for the tip! I checked and didn't reproduce this error. My car has every single symptom described by others, who were only able to have it fixed once RCM was replaced (~10% battery per day while idle, auto-pilot getting disabled intermittently, no battery drain after firmware update, only after it's been driven at least once...)
@lunaj23 hoping you won't mind sharing which SC you wen to... Thanks again!