1420 New Audio driver update

Hi all, I have had my dell inspiron 1420 notebook for 3 months now and have never had any problems with the audio until 2 days ago. a pop up from the dell support center said that there was a new audio driver a SIGMATEL STAC 92XXX C-Major HD that needed to be installed, and since i'm a college student and listen to music on my computer all the time i thought it'd probably be beneficial to install this update. wrong. Once i downloaded and installed the new driver i started to notice problems almost immediately. The speakers that i have plugged in to my computer would not play when plugged in to the left headphone jack on the front panel, fine, i can deal with that since they did start to work on the left panel. But now when i unplug my speakers, no sound will some out of the speakers installed in my system. this really troubles me. i opened up the sounds playback menu and it says all the systems are working correctly, but the system speakers still aren't playing. I have also noticed that the little blue bar that shows you how loud your speakers are when you're adjusting them has stopped appearing at the top of the screen. does anyone have any ideas about how to get this new high definition stuff off and return to my old settings without the update? i tried removing my audio driver completely, but when i restarted it just installed the new one. can someone help? thanks, MT