Check supply voltages of VDD_AUDIO, 5V_VCC and 3V3_VCC with a voltage-meter.
There may be a problem in headphone connector or headphone detect circuit (when
headphone is connected, speakers are automatically muted). Measure voltage at
HP_DETECT pin, it should be 3.3v.
25.8 No sound problem at headphone
Problem: No audio at headphone output.
Check HP detect pin, when headphone is. Check 5V_VCC and 3V3_VCC with a voltage-
meter.
25.9 Standby On/Off problem
Problem:
Device cannot boot, TV hangs in standby mode.