LG K4 2017 User Manual page 105

Message
Files do not
open
The screen
does not turn
on when I
receive a call.
No sound
Appendix
Possible causes
Unsupported file format
Proximity sensor problem
Vibration mode
Possible corrective measures
Check the supported file
formats.
If you use a protection tape
or case, make sure it has not
covered the area around the
proximity sensor. Make sure that
the area around the proximity
sensor is clean.
Check the settings status in
the sound menu to make sure
you are not in vibration or no
interruptions mode.
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