Toshiba X870 User Manual page 152

Problem
Annoying sound is
heard
External monitor
Please also refer to
with your monitor for further information.
Problem
Monitor does not
turn on
User's Manual
Procedure
In this instance you may be experiencing feedback
from either the internal microphone or an external
microphone connected to the computer - please
refer to Sound System and Video mode
information.
Volume cannot be adjusted during Windows start
up or shut down.
If you are still unable to resolve the problem,
contact TOSHIBA Support.
Operating Basics, and to the documentation supplied
Procedure
After confirming that the monitor's power switch is
on, you should check the connections to make
sure that the power cord/adaptor is firmly
connected to the monitor and to a working power
outlet.
for further
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