yellow marks different computer

[ImnoGuru]

If you're replacing a sound card...why not try to find out what's wrong with your current one first?  It looks like you're having a driver issue with the one that's currently in your system.

Your questions Saviour lead me to think.....
So lets stand back for a minute and have a look.

If a motherboard has a sound jack attached and visible from the rear of the case, to connect say speakers, to spk jack and a microphone to the mic jack and so on,... then does it also have to have some circuit board attachable unit actually in/on the motherboard, (eg like the one pictured but the proper one)?

 and if it doesnt is this called the onboard sound...

or is the mere fact that the computer has these insertable sockets for line, mic auxillary and speaker at the rear of the case mean that it has a sound (card/system).

or am I just not seeing "the sound card". The view of photo's above show slots and the case cut outs and no added CARDS, also the cut outs are all intact, so no units have been installed in the slots that require the removal of any cut out.

My neighbour is back now, (the one I bought the computer from), so I can ask him some of these questions and maybe get a sound card from him to install. I'll ask him next chance I get.
Thanks again everyone.I'll get back to you when I get a sound card.

[ImnoGuru]

CURED.. my neighbour had a little USB plug-in device, no bigger than your thumb, called "3D SOUND" cost $5.00 AU.
The computer plays sounds through all modes. So it seems that there is a problem on the motherboard with the sound system.
I apologize for the long delay in response, work got a little hectic for a while....( got to get it while its there ) but thank you all for your support with these issues.
Each answer should have worked in their own right, however I think there is some issue with the motherboard that caused this problem in the first place.

Regardless we found a satisfactory solution to the problem, once again thank you all.