Just got back home after a work trip and getting caught up on this thread.
I had a problem with transformer hum on the MKIII and sent it in. Steve fixed it. No transformer hum now. I asked DeVon about it and she mentioned a loose wire inside the Taboo. Still have the low hum from the use of new lucid mode. It is not volume dependent which is nice because at normal listening levels it can't be heard. Mainly heard during low level passages. Old lucid mode is near black in background so I'm sure it isn't the tubes but rather something else going on. I don't own any high impedance or balanced headphones to know whether this hum is less present in other operations.
On a separate note, thinking of picking up a used Bottlehead Foreplay III preamp. Anybody every try them? I know they are considered very good. An opportunity to try what a preamp can do in line with the MKIII.
Regarding the hum, I put my ear to the transformer last night (with no music playing) and it's definitely humming loudly. @ Those of you who aren't getting any hum, does yours do the same?
Also, mine came with the Valve Art 274B rectifier - which isn't the one mentioned on the product pages. Did everyone else get this rectifier too?