Sony PCG-XG28 Primary User Manual page 107

If nothing occurs doing the step above, press the power button for
more than four seconds to turn off the computer.
If the pointer does not move while playing a disc, press
Ctrl+Alt+Delete to stop playback and restart the computer.
Some titles require specific files that are located on the application's
CD-ROM. Insert the disc and try starting the program again.
Make sure you place the disc in the tray with the label side facing up.
If the diskette is write-protected, disable the write-protect feature or
use a diskette that is not write-protected.
Check that the diskette is properly inserted into the floppy disk drive.
If the built-in speakers are turned off, press Fn+F3 to turn on the
speakers. You can also turn on the speakers using the Jog Dial control.
If the speaker volume is turned to the minimum, press Fn+F4, and
then press to increase the volume or you can use the Jog Dial
or
control to control the volume.
If your computer is powered by batteries, check that the battery packs
are inserted properly and that they are charged.
If you are using an application that has its own volume control, check
that the volume is turned up.
Check the volume controls in Windows.®
If you connect external speakers, check that the speakers are properly
connected and the volume is turned up. If the speakers have a mute
button, make sure it is off. If the speakers are powered by batteries,
check that the batteries are inserted properly and that they are
charged.
If you have connected an audio cable to the Headphone connector,
disconnect the cable.