"White noise" in speakers. Tubes?

I recently bought a Audio Research REF 1 tube preamp. I notice "white noise" (low level constant static) emanating from both speakers, with a bit more prevalence on the left speaker. The seller indicated that the tubes were around one year old. Could this noise be from the tubes (6922's) needing to be replaced? Have any of you experienced this before? Associated equip: Plinius SA100MKIII amp, Meridian 508.24 CDP and Dynaudio Contour 3.3 speakers. Cables: NBS Monitor I XLR interconnects, and NBS Monitor III speaker cable. Cords: Shunyata Vipors (CDP and Preamp) and Black Mamba (amp) into Richard Grey's Power Plant
Hi Rosstaman Yeah I think it might be a gassy tube. I am hearing the same as you only it's only comming from the right spkr. The only thing I can suggest is to change your 6922's. My disadvantage is that I have a tube pre and amp, so I have two units that might be at fault. Won't give up my tubes however-love the sound! Best of luck
Yep, tubes. The easiest way to determine for sure whether it's the tubes that are not putting out equal "tube rush" (which seems to be unavoidable to some extent) is to simply switch them from the left to right channels (making sure to move only one pair at a time) and see whether the offending noise moves with them. If so, there's you culprit. Various folks are available for purchase of "DAC grade" mached tube pairs that will be more likley to be both quieter and more evenly matched. I've experimented with a number of NOS tubes in my preamp, and, although they seem to all start out quieter, they all seem to end up acquiring that signature tube rush after a bit. (By comparison, the tubes that I have put in my CD player have all remained dead silent, so I am not sure whether it is a product of the preamp or the tubes I have put in it). In any event, it's relatively simple to indentify the noisey bits and then you're off on the glorious road to tube rolling. Enjoy.