Asus P5N-D Audio troubles

Hello, I am getting annoyed with my computer, every few days it corrupts its self, that i can deal with but i have a really annoying problem, which is easily avoidable but i wish to fix it...

My build
Mobo: Asus P5D-N
Ram: Cant remember the details but its low end 4gb
PSU: HighPower 560w Modular
GFX: 1x PCI-e GeForce 9600gt 1gb
CPU: High End Intel Pentium Core 2 Duo 2.8 ghz Overclocked to 3.36ghz
HDD: 1x 500gb WD Middle Range, 2 Partions
OS: Windows XP 2 Fresh install, 28days left before activation
Speakers: 5.1 Logitech 4-5 month old

Im not sure if this is a driver related problem or hardware, The audio drivers are up to date

Heres the problem... When the Master volume is turned up max the speakers begin to beep at a constant rate at a high pitch, this can be avoided by turing the volume to below 75% but what whould cause this or how would i go about to fix this?