Pro Junior tube with hum in V1 no hum in V2

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I bought a used set of  (2) EL84 and (2) 12AX7 (three JJs and one russian tung)
To test them I installed one by one in my Pro Junior
They did well except the Tung Sol 12ax7 in V1 created a terrible hum (tried several times) but was fine in V2.
It also seemed to work fine as V1 in a champ. No input in either case.
Any thoughts why the tube would work in V2 but not in V1?

BTW, does the forum prefer new topics for each subject? or keep issues together with the same amp?
https://el34world.com/Forum/index.php?topic=29413.msg323749#msg323749