4.No sound
One or all signal source without sound.
NO
YES
NO
YES
NO
YES
No sound
Signal source
NG?
Check input
signal and
terminal
Change signal
source and
terminal
Speaker
connections
OK?
Replace/
reconnect
speakers
AMP I2C signal
OK?
Defect on AMP
unit
Check IC & I2S
signal circuit
Replace AMP
IC/main board
Upgrade
software
Replace main
IC/main board
No sound
40