06-17-2014 05:59 PM
Hello brl, welcome to the HP Forums.
It appears that since the last Windows 8 update your mute has been stuck on. I will try to help you with this.
I would suggest to start with a system restore to a point prior to the update.
Using Microsoft System Restore (Windows 8).
If that fails you could then go into device manager and uninstall the audio driver. Then reinstall it. Realtek High-Definition (HD) Audio Driver.
Please let me know how this goes.
Thank you for posting on the HP Forums.