I have had this problem. After lots of research I found that the tube phono stage as shipped by the factory had an input resistance that did not match my cartridge. The factory has sent me new resistors to be soldered in that will match my cartridge. I haven't completed this yet & so can't say that it solved the problem, but if you e-mail me I'll let you know if it did in a couple of days. (my phono stage is a Cary PH-301)
Phono Preamp Tube Rush
I HAVE A ROGUE AUDIO 99 WITH PHONO STAGE.AT 12 olock I get a low level hiss.Can only hear it with no music on,between tracks and during quiet passages.Rogue rep. told me to get quieter tubes@$15 each.Is tube rush normal.I spent big bucks for this preamp.Am I over reacting. Thanks all!