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SAE P102 preamplifier Schematic needed

Hi All, I have a preamp that has trouble with the LED readout for the volume and the standby LED are not working. The volume colon dots work but there is no voltage to the segment display. I swapped it out for a known good one and still the same problem. The Standby LED is good also but when turned off there is no voltage to activate it. I was wondering if anyone had an idea where I should look and if anyone could share a schematic so I could test it properly. Every other feature and LED display works fine.

Can anyone help me out here? My preamp lost the volume leds and the standby led. Although they test good, it must be a driver or relay. They were intermittent for a while now fully dead. Thats to say that once in a while the standby led would come back on, and if I turned it on the volume leds were back but then it would vanish again. Im sure its some common voltage or ground link thats doing it or a sticky relay. Please help.