Toshiba NB520 - Manual (Page 63)

Dolby Advanced Audio supports the internal speaker only and does not
support any other speakers. Please do not enable Dolby while you are
using an external speaker such as the speaker of TV connected to the Intel
® WiDi.
Notes on Using Microphone
You can use the built-in or an external microphone that connects to the
microphone jack to record monaural sounds into your applications. It can
also be used to issue voice commands to applications that support such
functions (built-in microphone is provided with some models).
Since your computer has a microphone and speaker, "feedback" may be
heard under certain conditions. Feedback occurs when sound from the
speaker is picked up in the microphone and amplified back to the speaker,
which amplifies it again to the microphone.
This feedback occurs repeatedly and causes a very loud, high-pitched
noise. It is a common phenomenon that occurs in any sound system when
the microphone input is output to the speaker (throughput) and the speaker
volume is too loud or too close to the microphone. You can control
throughput by adjusting the volume of your speaker or through the Mute
function in the Master Volume panel. Refer to your Windows
documentation for details on using the Master Volume panel.
Video mode
Video mode settings are configured via the Screen Resolution dialog.
To open the Screen Resolution dialog, click Start -> Control Panel ->
Appearance and Personalization -> Display -> Change display
settings.
If you are running some applications (for example a 3D application or video
playback and so on), you may see some disturbance, flickering or frame
dropping on your screen.
If that occurs, adjust the resolution of display, lowering it until the screen is
displayed properly.
Disabling Windows Aero TM may also help correct this issue.
Computer Handling
This section explains computer handling and maintenance.
Cleaning the computer
To help ensure long, trouble-free operation, keep the computer free of dust
and dirt, and use care with all liquids around it.
NB520 series
User's Manual 3-29