Schematic diagram for Tascam 22-4

Hi,

I need help with the detailed schematic diagram for Tascam 22-4.
I cannot find it and maybe anyone can help me.

I have a problem with one channel and the defect is on Rec/Play PCB. I need the detailed schematic diagram.

I found one on Elektrotanya but is not a detailed one.

Thank you for your help.