soundcraft 2400 channel strip help SOLVED!

hi everybody.
I have just finished wiring a soundcraft 2400 channel strip up (thanks NRG recording for the boards!), but there is a problem on the microphone input stage.
there is a distortion phenomena happening right after the array of transistors named TR1 through TR6 which are responsible for the gain staging.
the picture below shows the distortion, which is also gain dependant,
on my scope (TOP scope Collector of TR6, BOTTOM scope Input signal to the channel) .

to make sure there wasn't anything else loading the circuit I momentary unplugged all the OPamps following that stage.

Could this distortion be due to a bad transistor?I wonder if just a bad one will compromise the functioning of the entire stage.

any help will be much appreciated..

here is the scope picture


and this is the schematic

BUMP!

Try to start with only one transistor on each side (one@TR1-TR3, one@TR4-TR6). If there is a bad transistor maybe you'll find him that way!?

Which transistors did you use? 2N4402 or BC560 or any other PNP types?

Hopefully the genitals on scope 1 will turn into boobs like on scope 2 then. :grin:

Make sure the transistors are in the correct way, there was an error on the layout diagramme.

Peter

The pinout is the same for BC560 and 2N4402.
There was a different layout so it is possible to use BCxxx transistors based on the second pcb.

thank you guysroblem solved.
bad solder joint on the gain pot.
silly mistake!
thank you for your support!

Best,
Mattia.