LC-46SB57U/LC-52SB57U
6 – 13
No audio signal at Digital Audio Output terminal (Analog sound heard)
No INPUT-5/6/7/8 (HDMI) audio.
No audio at digital broadcast signal reception.
If no video appears, refer to “No external input video (HDMI)
[INPUT-5/6/7/8]”.
If no video appears, refer to “No video at digital broadcast signal
reception”.
Is there the SPDIF signal output (CPU-SPDIF-OUT) at pin (J28) of IC8001 (CPU)?
YES
NO
Check the IC8001 and its peripheral circuits.
Is there the SPDIF signal (CPU-SPDIF-OUT) input at pin (1) of IC1304 (SPDIF-BUFFER)?
YES
NO
Check the line between IC8001 and IC1304.
Is there the MUTE signal input at pin (2) of IC1304? (usual: High, Mute: Low)
YES
NO
Check the MUTE_A_ALL and AC_DET signals, and their peripheral circuits
(Q1304, D1301, D1310, etc.).
Is there the SPDIF signal input at pin (1) of D1306 (SPDIF-OUT)?
YES
NO
Check the speakers and the optical cable.
Check D1306 and its peripheral circuits.
No optical output under the following conditions as per HDMI requirements.
* Audio contents protected.
* Audio frequency beyond 48kHz.
* Audio bit length beyond 16bits.