F5Turbo Illustrated Build Guide

I measured for continuity between the grounds of my inputs and outputs and the chassis, and after a couple of seconds there is, but at 9 Ohm so through the resistor of the ground lift I guess. There is another thing: every time I switch on the amp with sources connected and running, there is a 'shivering' going through the chassis and I hear mechanical hum from the (800 VA) transformer. Then after a little while I hear the hum through my speakers (and no more mechanical hum). Could this have to do with my problem?
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The shudder at initial power-on is probably magentisation current and is not related to electrical hum in most cases.

I see you've used fairly thick unshielded twisted pair for the input signal, I've not had much success with anything but screened pair with a grounded screen.

Do you have access to a portable source (not connected to mains)?
I might have found the cause of the problem: the right pcb gets the correct voltage (63 V between + and -), but the left almost nothing (a couple of mV), both with a not insignificant ac part that I'm not being able to measure with my dmm. I used solid core copper wire for the connections between the psu en the pcb's, and that has underwent quite some stress during the build. I suspect one or more of the wires to the left pcb is (almost completely) broken..
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