Problems, Lots of hum. Can't find a schematic on this one. It uses 2 BEU7's 4 12au7's and 2 7191's for the output. I can remove every tube except the outputs and still hum. Checked a lot of voltages and everything seems ok. Still hum. Replaced the 20uF filter caps. Still hum. Tried a new set of outputs. Still Hum. Any ideas? There's not that much to it.