Definitely sounds like your just getting leakage/pickup on that pin. The inputs are considered "High impedance" and will only drain slowly so if there is a lot of energy floating around (and its a ubitx we know there is!) it will definitely pick up some of that and store it in what little capacitance the wires provide. The fact that is is consistent is amusing at least :)
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Tim Keller - KE2GKB
