Toshiba Satellite Pro C50-A - Manual (Page 85)

When audio power management is disabled, the button is black and
concave.
Speaker Configuration
Click the Auto Test button to confirm the internal speakers or the
headphone sound is coming from the right direction.
Default Format
You can change the sample rate and bit depth of sound.
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), 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.
User's Manual 4-43