Samsung DSR9500EMVIA - Manual (Page 35)

Troubleshooting
4-4 Samsung Electronics
NO SPDIF OUTPUT
R430 is 5V? Check R430, SMPS.
Yes
No
Data waveform
occur at R431.
U750 Data, CLK
: 5, 6, 7, 8.
Yes
No
Check 750.
Yes
Check J801.