Sunn Beta Preamp volume issue

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Sunn Beta Preamp volume issue

Sentenza
Hello, i'm having an issue with my Sunn Beta Preamp build:

https://tagboardeffects.blogspot.it/2016/03/sunn-beta-preamp.html

the output volume is very low and the level (volume) pot works backwards.
If i remove the TL071, the volume issue is solved but the level pot is not working. I've tested the circuit with an audio probe, if i take the signal after the 12k resistor that leaves that OUT 2 of the 4558 on the top right corner, the volume level is good and the level pot works as it should.

The diodes are 1n456A:
https://www.musikding.de/1N456A_1
On this schematic they are 1n458A:
http://viva-analog.com/wp-content/uploads/2016/08/SUNN-Beta-Lead-pre-amp-schematic.jpg

I'm powering it using Mark's bipolar converter:
http://tagboardeffects.blogspot.fr/2014/01/bipolar-voltage-converter.html
and then connecting it to the Rusty Voltage Converter:
https://tagboardeffects.blogspot.it/2014/03/tronographic-rusty-box.html

V+ 13.70 V
V-  13.66 V


Here are the voltages:

First 4558
1) -0.297 V
2) 0 V
3) 0 V
4) -13.63 V
5) 0 V
6) 0 V
7) -12 mV
8) 13.68 V

Second 4558
1) 0.242 V
2) 0.242 V
3) 0.242 V
4) -13.15 V
5) 0 V
6) 0 V
7) -16 mV
8) 13.46 V


Third 4558
1) 0.14 V
2) 0.14 V
3) 0.14 V
4) -13.17 V
5) -12.88 V
6) 7.83 V
7) 13.45 V
8) 12.63 V


TL071
1) -13.20 V
2) 8.27 V
3) 0 V
4) -13.20 V
5) -13.20 V
6) - 11.90 V
7) 13.46 V
8) -0.17 V


4069UBE
1) 0 V
2) 7.69 V
3) 0 V
4) 7.56 V
5) 3.87 V
6) 3.97 V
7) 0 V
8) 3.85 V
9) 3.83 V
10) 3.89 V
11) 3.88 V
12) 3.85 V
13) 3.90 V
14) 7.70 V





Thanks!