Hi NineKei,
I understand you are having issue with the audio on your HP Envy Dv6. If you download are run the HP Support Assistant, it is software program designed to help you keep your computer in working order.
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c03467905&lc=en&cc=us&dlc=en&product=4308434
If that does not help you could try to uninstall IDT High-Definition Audio Driver and reinstall from this link.
Hope this helps.
Thanks