Toshiba Portege R930 - Manual (Page 170)

Problem Procedure
Annoying sound is
heard 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 in Chapter 3, Operating
Basics for further information.
Volume cannot be adjusted during Windows start
up or shut down.
If you are still unable to resolve the problem,
contact TOSHIBA Support.
External monitor
Please also refer to Chapter 3, Operating Basics , and to the documentation
supplied with your monitor for further information.
Problem Procedure
Monitor does not
turn on 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.
User's Manual 6-16