Tube Amp Noise with Klipsch Cornwall II

Sell Rogue.
As previous posters mentioned, your vintage Klipsch will pick up virtually any minor oscillations of the amp.
Technically I would experiment with adjusting feedback (obviously lowering the gain factor which may significantly help avoiding noise) along with adjusting bias current to the specified level of the THD which is more like re-tuning the amplifier.

Some suggestions. I use a pair of Klipsch Fortes, which are a bit less sensitive with your Cornwalls, with tubes and have no noise issues at all. But, I have a few suggestions for you. First is to really establish that it is the amp that is causing the trouble. Short one set of inputs and turn the selector switch to those inputs. If the noise is still evident your issue is the amp. If it is not, then the issue is your source. Buying quieter tubes is certainly an option, but an alternative is to call Rogue and find out if they can diminish the gain in the amp. You may find that this really knocks the hiss down, and it may also help you to advance the volume knob into the linear part of it's range, as now you are probably using it at the very beginning of it's travel, which sounds the worst and usually has the worst channel matching as well.

I am totally not up-to-date on tube equipment. Are test points and adjustment pots easily accessible??
I like the 'tune up' idea before any tube changes.

Lowering the gain of the amp sounds too much like a re-design?

I know this is a BAD thing to say, but SS?

Magfan,
Adjusting a gain very often is a feature of amplifier without any kind of re-dedign. It's rather 'adding' to an existing functionality and making the unit less-depended on tube quality. Most-likely, if higher quality tubes are purchased at the more than half-price the amp worth, the noise may still be an issue.
Tube amps are flexible in general in terms of adjusting a gain and/or lowering input sensitivity. The pot you need to install instead of feedback resistor to figure out the value at which the noise dissapears. Adjusting bias may or maynot be necessary neither on small signal or power tubes.

Congrats on your new speakers...I used to own Chorus in the late 80's. Klipsch'r really great w/the right tube amp. The Rogue is decent & very ballsy but noisy & somewhat unrefined & not quite 20/20 vision if you know what I mean. I was once the proud owner of a new Cronus hot-rodded to the max by Rogue w/their choice NOS tubes & it was somewhat noisy even w/my 92dB speakers & the bleed thru on the speakers while using the headphone section drove my better half crazy late at nite. I think if you find something more refined & perhaps triode driven you'll be in heaven. I'd love to try something like an Almarro 318B w/Corns....good luck.