Update- I put in the stock EH tubes and the preamp works perfectly, no noise. Mark at Rogue has since checked out the NOS I sent back and he finds nothing wrong with the tubes. No noise, no microphonics. Is it possible for a tube(s) to be microphonic and then not be? I also had put in a new CDP into the system and new power cord to the CDP earlier in the day before the tubes became microphonic. Could this have caused a tube issue, maybe some sort of electrical interference? I'm baffled by this and wonder if anyone else has had a tube issue similar. Rogue is sending a new set of NOS and I should have early next week, hope no issues.thanks for the help.