BOOT CAMP 044
SOUNDING OUT YOUR PC PART 2
How much do you know about the audio system on your PC? Probably
not much, apart from the fact that sounds come from a pair of speakers plugged
into the back of the machine. Most of the time that's all you need to know,
Windows 95 has tamed a lot of the PC's early difficulties with sound but things
can and still do go wrong. This week we're looking at some common sound faults
and how to put them right. So where do you start?
If you get no sound at all, apart from boot-up bleeps from
the internal speaker (and the PC appears to be behaving normally) check the speakers.
A lot of PCs nowadays come with 'active' or powered speakers with built-in amplifiers.
After inspecting the plugs, switches and sockets, and verifying the speakers
are working by plugging them into the headphone socket of a radio, personal
stereo or hi-fi, you can turn your attention to the PC.
Did you spot any unusual messages during boot-up? Re-boot
and this time watch closely. You PC carries out a range of diagnostic checks
prior to and whilst loading Windows, and this includes tests to make sure the sound
card and its drivers are all present and correct. If the problem is serious the
Windows boot up sequence will pause and you'll see an error message, but not
always, or it may just flash up quickly on the screen. If you spot anything
suspicious make a note of it. If you can't fix the problem it may prove useful
to a service engineer or Helplines.
If you didn't see any messages look for any obvious causes, make
sure the sound hasn't been muted or the volume turned right down. It's amazing
how often simple faults are overlooked… Load an audio CD in the CD-ROM drive
and see if that works; if it does go back and check those volume and mute
settings again. If you hear normal PC sounds but nothing from audio CDs then it
could be due to a loose or disconnected cable between the drive and the soundcard
or motherboard; we'll deal with internal examinations in a moment.
If you have Windows 98 start the Sound Card Trouble-shooter
utility, simply type 'sound' in the Windows Help Index text entry field. The trouble-shooter
uses a question and answer routine to help track down the fault. Windows 95 users
should open Control Panel (Start then Settings), click on the Sounds icon and highlight
one of the entries in the Event window with a little speaker icon. Now click on
the triangular 'play' symbol next to the Preview window.
If that doesn't elicit a response double click the System
icon in Control Panel. Select the Device Manager tab and scroll down to Sound
Video and Game Controllers, if there's a problem with the sound card driver or the
card you will see a small yellow circle with an explanation mark next to it. Click
on it and this will bring up a series of tabbed dialogue boxes. A brief
description of the problem may appear under the Properties, Profiles or Performance
tabs or buttons.
If there is a fault with the driver software you can have a
go at re-installing it, by clicking on the Update Driver button, and following
the instructions. Alternatively start the Windows Device Conflict trouble-shooter;
to find it open Windows Help and type Conflict.
Installing or re-installing a driver is normally quite straightforward
just follow the instructions; you will need the original sound card driver disc
or one of the standard drivers on the Windows CD-ROM. If the fault lies with the PC not recognising
the soundcard then you will have to use the Add New Hardware Wizard in Control
Panel and allow Windows to find and re-install the card. If after all that the
problem remains there are two further possibilities.
The least likely is a failure of the actual sound card, it
happens but not very often. The other more likely cause is the sound card working
its way loose in the motherboard expansion slot, or dirty contacts. Either way it's
a lid-off job. Incidentally, not all PCs have sound cards, there is a growing
trend to incorporate the audio circuitry into the motherboard, in which case a
hardware fault could mean replacing the motherboard, or installing a separate sound
card. Diagnosis and repair is best left to an engineer.
If you are confident about opening up your PC take the usual
precautions. Disconnect it from the mains, or you can leave the plug in, but
make absolutely sure the socket is switched off. This ensures the PC's
metalwork is connected to Earth and will safely dissipate any static charge
that may have built up on your body or clothes. Always touch the case
metalwork, before handling anything inside the case. Locate the soundcard, it's
the one where the speaker and microphone cables go.
If you're having trouble hearing audio CDs look for the
cable that goes from the CD-ROM drive to the sound card (or motherboard). The
cable may be adrift, if so it should close by and fairly obvious to which
socket it belongs. Check also the connections on the back of the CD-ROM drive.
If you're tracing a PC sound fault remove the plugs from the
back of the soundcard, and the CD-ROM cable, after taking a note of where each
one goes. Remove the screw holding the card in place and prise it out of the
motherboard socket. It may be quite tight so use a gentle rocking motion, don't
try levering it out with a screwdriver, you will damage something! Once the
board is out inspect the row of contacts, if necessary wipe them over with a clean
dry cloth. Don't touch them, sweat and skin oils can cause contact problems. If
they don't look clean and bright you could try rubbing then gently with a dry
nylon scouring pad. Re-seat the board, not forgetting the cables and retaining
screw and try again. If the problem persists it's time for some expert help.
A small program that tell Windows how to communicate with a
particular piece of hardware, like a sound card
An error caused when the computer tries to access a device
that it doesn't fully recognise, has been identified incorrectly or allocated
resources used by other devices
A simple helper program that guides you through the set-up
routine for a particular feature or application
Your multimedia PC has a sound system that is capable of hi-fi
performance but you're never going to realise anything like the full sonic
potential of audio CDs and games with those speakers… The speakers supplied
with most PCs have the acoustic properties of baked bean tins. If you've got a redundant
hi-fi system or some half-decent speakers lying around, try connecting it to your
PC and hear the difference! The soundcards used on most PCs have an amplified
output and can drive speakers directly. Suitable leads are available from
electrical accessory dealers. Maplin Electronics (01702 554000) have one (Part
no. VL42V) costing £2.99. Make sure the speakers are at least a foot away from
the monitor screen, otherwise the speaker magnets may cause colour staining on