Noise From New Tubes

I have just installed a pair of RadioTechnique 12AU7's in my CJ PV10A and am experiencing "static" type noise. I removed them and used a can of compressed air to remove any dust, debris, etc, but the noise is still there (although much less so). Might these tubes be "bad"? Are there any other tricks I can try to clear up the noise? Could there be a problem with the "sockets" in my pre-amp???

Thanks!!!

Brad Day
Atlanta, GA