Electrocompaniet AW 180M adjustments

[Elan67]

Hi all,
I almost fixed a (...completely...) broken EC AW 180M.
Adjusting dc offset & bias was quite trivial.
R44 for bias current (9-8.5mV across 0.2 ohm restistor = 45-42.5mA as the working one)
and R7A to null dc offset before ouput relay.

Now there is a third trimpot (R6P) on the so called "Sister Board" near IC protector.
EC firmly but kindly but refused to give me any help or hint .
Amplifiers measures and sounds good but ...
Is there someone who can give me any help?

Thanks in advance

[hollow_man]

Possibly an adjustment for the output overcurrent protection.