I'm having problems with my 5.1 sound!!!!

Okay here is whats been happening I awhile back i was using the Windows 7 RC i recently got Windows 7 Ultimate which is perfect but except for one thing my sound is not working properly i have logitech 5.1 sorround sound speakers when i play music it wont work no sound even on videos but when i load up the sound drivers and go to test my speakers only a few of the speakers work but the thing is it plays sound but when i go to play music nothing comes out i click on the sound icon in the system tray and it says that sound is playing i turned everything up still nothing i disable some of the recording devices i use a dell Deminson 4600 recently upgraded its hardrive and ram but i had XP after the upgrade and everything was working perfectly sound was good graphics drivers were good but this is driving me nuts!!! i really dont want to go back to xp after waiting about 3 hours to install windows 7 is there a fix around this or something??? i have try everything even installing vista drivers i use sound max drivers by the way. i reinstall windows 7 twice still no sound i really hope someone can help me sorry for my bad grammar and just kinda typing this up with thinking.....

help me please =[

thanks

also i didnt upgrade the pc i just reformatted it and windows 7 RC sound was working fine

Here's my temporary fix. Uninstall your sound card's drivers, and restart the computer. Let Windows auto-install the drivers. Then it should work.

The catch is, as soon as you restart your computer, your sound card will be back to not working properly!