I upgraded from from vista to windows 7 and have a few probs?

Hi could someone pls tell me what is the best option i can do, i have a acer aspire m1610 desktop my OS was on vista but i done a full install of windows 7, my audio is up the wall in cracking and ect, also dont have stereo mix which i use often, i never got any recovery disc when i bought the pc 4 years ago, its in good working order and dont really wanna buy a new one, my only option is to go bk to vista as i know everything works fine and dandy, i have tried so many solutions to get my audio/stereo mix to work but nothing, i have looked on line for a recovery disc on vista for my m1610 pc but says it doesn't contain a OS, pls what can i do