Recording microphone and computer audio at the same time in Windows 8

Voicemeeter is typically made to allow that ! It is a virtual audio device Mixer able to mix/route several audio sources (for example your MIC and computer sound) to different audio points (for example to your speaker and to Audacity or whatever audio recorder applications)! More info and complete documentation on www.voicemeeter.com (get latest version on their facebook/G+ pages). Many tutorial on youtube...