Tube and Tube Socket Cleaning


I have a pair of RT 12AU7's of which one of them is noisy when powered up. I have switched it from side to side in my pre-amp (CJ PV10A) and the noise follows. I sprayed a great deal of compressed air into the tube socket and around the prongs of the problem tube and this has diminished the noise greatly, but not completely. I spoke with the dealer and he advised me to take a fingernail file and gently file the prongs on the problem tube. Any thoughts on this???
He also mentioned that there were tube socket cleaning kits available. Has anyone had any experience with these or can anyone recommend one?

Thanks!!!

Brad Day
Atlanta, GA

PS My searches on Audiogon for this information did not turn up any matches.
bday0000
Thanks, Detlof. Also, did you use a metal nail file or a wooden one with the sand grain on it? And, where might I find Kontak or Pro Gold locally (Atlanta)?

Thanks again.
sounds to me like the tube is bad, not the socket. It follows from side to side when moving that tube? Send it back.

-Ed
what kind of noise is that? microphonic? ac? hissing?
i just realy wonder how the other socket isn't noisy being basically as "dirty".

the cleaning doesn't help everytime as in this funny story:

a blondie is trying to start up her malfunctioned mercedes without any success. another blondie in jaguar drives by stops and trying to help:
--did you wipe your dashboard?
--yes
--did you wipe your head and tail lights?
--yes i did!
--did you clean your rims?
--certainly!
--and still you can't start it?
--no
--sorry, can't help you than!

as to cleaning tube prongs and sockets it's considered to be a basic hyegine that you should excersise once in approximately every 300 hours. i use kontak with supplied wire-shaped brushes that can penatrate even sockets for small signal tubes all arround the sockets and prongs. if the oxiding is visible it's probably fine to use the fingernale file while i use de-oxiding spray and still try to remove it the "gentle way".
Rt 12AU7 are a noisy tube.Most of whats around and comming out of the left Coast is pretty noisy period
I use two methods. For tube pin cleaning, a common pencil erasor works well. Also, one of those fiberglass cleaning tools available from Radio Shack will take the crud off the tube pins. The tool is also small enough to fit inside the tube pin sockets as well. Just rotate the thing a few times and the flexible bristles will clean the pins and sockets to bright metal without removing any material from either. I chuck the pen shaped tool inside my rechargeable drill for stubborn cleaning jobs. Follow-up with deox-it or similar for a years worth of scratch-free listening.