Conrad Johnson PV-14 background noise


I noticed a faint background hum caused by my CJ PV-14 (because there is no noise when I turn on the power amp only), it is not obvious but you can hear it when you get really close to the speakers. I have tried a set of new tubes but the noise did not change. Anybody has experience to share?

Thank you!
If you want super quiet, get a solid state preamp. My C-J PV5 has some noise too. But I have to stand real close to my speakers (6"). If you can't hear it at your chair, don't worry about it.
I just purchased a PV14L from an A-gon member and this unit has no hum at all. The unit came with a total of 4 tubes and 2 of those had tube hiss but after sorting through the tubes I came up with 2 that are nice and quiet. You may want to try a cheater plug and see if that removes the hum.
try plugging electrical cables into different sockets you may be getting a ground loop hum especially if you are using a sub
Thank you for your advises,

Dusty, I have to be very close to the speakers, so I guess it is not unacceptable

Vernneal, I will try other sockets.

Rrog, No, I did not get it from CJ. I got it from Ebay. But the old ones I use are Mullard purchased from CJ and they have noise too. And I tried to call client service of CJ but its always answered by an answer machine.

Dwr,could you please elaborate a little bit what is a cheater plug?
The cheater plug just makes a two prong plug out of a three prong plug, you can buy them at a hardware store for under a buck. If you try this and it reduces or eliminates the hum, it could be caused by ground loop.
Have you replaced the electrolytic capacitors. That is the first thing I do after buying older equipment.
Rrog, it's a very feint hiss.

Orpheus, I have not replaced any of the capacitor. Do you suggest I do so? or it only applicable to PV12, no need for PV14?