Sound not working, help!?

Alright so the sound on my Compaq Presario CQ62 is no longer playing back or letting me record sound. I was recording myself playing guitar and it worked fine until one recording had no sound and then it said that no audio device could be found. When I hit OK, under the Playback tab in the sound device manager, speakers showed up as working and a microphone showed up as working under the Recording Tab. I had a Microsoft Fix program try to fix it, but it found no errors. I am really confused and don't know what to do. Could someone help me?