sounds like you do not have a compatable sound card on your machine,
you will need one or you'll have to use other software.
Contrary to popular belief you do not need to go broke to get
a soundcard these days."Mad Dog" makes a card called a 'Prowler"
which is 4.1 4-channel with a pretty good software package
including 5.1 emulation, about a dozen types of echo effects at
various levels, a "jukebox" and so on for about $20.00 at CompUSA,
while it is no "killer amp" the PCI card is simple and install and setup
are a breeze, it supports Directx and Creatives EAX. there is a surround
sound rear channel option for use while using headphones which is sort
of neat, while the sound quality is not "studio" level I have found the
card does a fairly decent job of games and musical playback. I have
this card in a old P3 500Mhz and it runs GuitarFX just fine but there
are little glitchy cracks and pops sometimes if I run thru the
Microphone input jack and have the echo part of the software
running, I believe this is more from the processor not being
strong enough than it is from the software package, go to windows
update for the latest drivers for this card based on the modem
MSP-5900 chipset.Hope this helps...
zippo...


--------- Mumufuk coments ------------------------
Thanks for good explanation!
Yes, I found that if I "overdrive" too much the output of my
SB Live I have the same discontinues or glitches or clicks in sounds,
so, overloaded sound card hardware can produce such kind of sound clicks.

FAQ about wdm drivers for sound cards was placed around 2 years ago at
http://guitarFXsoftware.com in FAQ section, also wdm drivers were explained
in this Yahoo Group many times, so, people could look into archive of
this Yahoo Group for info before ask again and again about wdm.