Switch/ Wiring Dilemma Hafler DH 101

My newly bought preamp is behaving a little weirdly.
When I engage the tone control switch It only adjusts the treble on one channel, the bass potentiometer does nothing.
When I disengage (defeat) the tone control the bass can be controlled but again on one channel? the treble is unaffected.

Obviously when the preamp's tone is in the disengaged mode it should do nothing.

The wiring on the switch in my preamp differs from the manufacturers Pictorial.
It appears the switch has been wired incorrectly judging by the photos, wires have been soldered to the wrong lugs, would this be the problem?

I know nothing about these type of switches and how they operate, could someone please enlighten me.
It looks like the wires on the bottom need moving up a lug?

This preamp came as a kit, I bought this second hand, I didn't assemble it.
 

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