Since your comment is conjecture I'll reply in kind. I agree about "case head failure" as the cause of the reciever failure.
Theres not enough definitive information in the original post to pinpoint the failure cause.
Too many variables to ascribe the incident either to the NO receiver and certainly not enough info to speculate what may have happened with a "low number" 1903 reciever
Respectively...IMO...Mike Haas![]()