Model X771
L3 Service Manual
23)
Speaker
Solution:
A-
Exchange the
speaker
to see if the problem is solved, if yes, It is the problem of the speaker;
B-
Check if U400,U401 have pseudo soldering or damage, if yes, Replace U400/U401
C-
Replace U300
Earphone
jack
L400
U300
L402
L403
L401
U400
U401