Here's the longer version.
Once I set it up, I noticed a smudge by the power light. It wouldn't rub off. Running my finger over it, it felt smooth to the touch so I knew it wasn't any kind of substance. Closer inspection revealed it was some sort of blemish (scratch, gouge, scuff, etc) and someone made a poor attempt to cover it up. Also, the screws that attach the faceplate to the unit look beat up. The black anodizing has been worn off and the exposed silver just stands out.
Appearence issues aside, I fired it up using the AKGs first. It seemed very quiet so I turned the volume knob up to about 12:00. It still wasn't loud enough so I turned it to about 2:00. Now I'm hearing distortion. Naturally, a little more volume just made the distortion that much worse. And when I say distortion, I mean distortion. A sloppy, garbled mess of overdriven noise. So I connected the Denons. Those were plenty loud with the volume knob in the 12:00 position but they distorted too with increased volume. Not as bad as the AKGs but it was noticeable.
So I contacted Jack. He inquired about shipping damage (which there was none), he asked if anything sounded loose inside (which it didn't) and then he asked me to remove the tubes and reinstall them (that didn't help). This morning he asked me to remove and reinstall one more time (I did) but that didn't help either. So naturally he asked me to ship it back to him and said he'll look it over and either fix it or build me a new one.
I'm still waiting to hear back from him regarding my last question which was "will you be issuing a call tag?". I don't want to be difficult but I really don't think I should have to pay to send this back to him. I bought an amp, I paid for its shipping to me and what arrived should've been a flawless working amp. What I got looks like a B-stock or a return and it doesn't work like I think it should. So I have to spend more money to get the flawless amp I should've had originally? I think not! If he tells me I have to pay for the shipping, I'm just going to ask for an RMA and be done with it.
In fairness, Jack is doing what he should. He's trying to make it right with me and for that I'm appreciative. But this shipping thing could be the proverbial straw.