One thing you need to do, if I am reading your post correctly, is to disable the intergrated sound. This the sound card that is part of the motherboard. I would not think this is causing the current problem, but if you install a sound card and the intergrated sound is still active you will probably have some problems with the sound.

I would uninstall both the sound card and the CD writer to take the system back to the point it was working. Check to make sure it is working correctly. Then install one at the time and bootup to check for problems after each one. This will help pinpoint what problems go with what.