Fare thee well (SOLD): Bottlehead S.E.X. 2.1 (upgraded)

I have a Bottlehead S.E.X. 2.1 that I built a couple years ago that has been sitting in a box since I moved a couple months ago, and will do so indefinitely. I love the sound and it was a very cool DIY journey, but it is too big and heavy to deal with anymore. I upgraded nearly everything I could except for the transformers. So connectors, capacitors, wire, volume pot (RK40 Black Beauty!) are all upgraded from original spec. It has the C4S power supply upgrade as well as the impedance boards allowing it to run balanced. It is in a headphone only configuration, so no speaker taps. Cosmetically, it is in pretty solid shape (I can dig it out for pictures if anyone is interested), with some minor dings and scratches that come with DIY and moving. Sonically, it has developed a hum that I can't sort out. When the music is playing at normal volumes, it isn't noticeable, but during quiet passages or when no music is playing, you can hear it. Doesn't change with volume.
I think a few members might have heard this at a past Chicagoland meet, but I'm not sure. Outside of the hum, it is wonderful sounding. Good power, good control, not overly tubey. Did really well with my HD800s.

So, I have about $800 into the amp, but due to the hum, which apparently might just require a couple little tweaks to fix according to some Bottlehead forum members, I am offering it up for half of that. $400. Less than the barebones kit. So if you have some DIY skills or can overlook some low level hum, this is a pretty good deal.

Like always, I am willing to be flexible on the price. This sucker is heavy, so continental shipping only for now.