Hi, Ted, welcome to RO. Nice website. I "operate" on tube gear and James Demeter makes some of the best. What type of "noise" do you have? Does it "spit", or is it a more constant type of white noise? You can tap on the tubes while they are warmed up and see if any are microphonic (you will hear them through your monitors), with the culprit tube being the offender.
You might try contacting Mr. Demeter to determine if he's had others with this problem. He can recommend a suitable fix, whether it is simply a replacement tybe, or a service rep ( especially if it's, say, a screen resistor or the like). In any case, if the unit is only a year old, I would contact them. There may be some sort of warranty time left on it.
BTW, are you using this rig on fiddle? His stuff doesn't get the attention it deserves, but I think that for bluegrass and other acoustic material, JD's rules...very smooth. He makes a pretty nice geetar amp, too! PEACE...

Demeter comp

So, moonbaby, the noise is related to recording. I only use the comp for vocals. There is not constant noise, but the output is very muddy and lo-fi sounding. To check the tubes, I would take the cover off the unit and tap them to see which produces sound through the output?
I bought this off ebay and don't relish the idea of a costly repair.
BTW, the Demeter pre works great for fiddle using SP C4 paired mics at an off-axis angle.

Thanks,
Ted Simon
http://www.downhomefiddle.com

Well, yeah, if noise from the unit is your complaint. Your complaint that it is "muddy" and "lo-fi" may still be tube-related. But it could be a variety of things. To start, tap on the warmed-up tubes with a pencil while the unit is hooked up to be monitored. Do you hear a metallic ringing or "thumping" when you do that? Then that tube needs to be replaced. Since the unit was bought used, there is probably no warranty left. But I would still contact JD.