No Check a route from a power supply circuit to pins above.
No Replace a electronic volume.
No Replace a electronic volume.
2 ch
Check DAC
Are the voltages of #7 and #8 5V?
Yes
Do pulse signals appear on #2 to #4 when Selector switch is changed? Do the digital data appear on #1, #26, #27 and #28 when the unit is set "TEST-4 00"?
Yes
Check periphery of on the the circuits Q400* and Q401*.