• If you brought a new machine with Windows 8 already installed, it is hightly likely the machine has a UEFI BIOS and a setting called Secure Boot is enabled.
• When Secure Boot is enabled our audio recording module is unable to hook into processes to capture the audio stream.
• To disable Secure Boot and allow audio recording perform the following steps.
• Press WinKey - C to display the Charms
• Click the Settings Charm
• Click "Change PC Settings" (at the bottom)
• Click "General"
• Scroll to the bottom and under "Advanced startup" click "Restart Now"
• Click Troubleshoot
• Click Advanced Options
• Click UEFI Fireware Settings
• Click Restart
• When the computer restarts you will be in the BIOS. The extact layout of the BIOS is manufacture dependent. Search for the Secure Boot option and disable it (its probably on a tab label Security or Boot), save the settings and exit.  
• HP BIOS instructions: http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?prodSeriesId=5295884&objectID=c03653226
• The machine will then reboot and audio recording will now work.