Audio with bad quality after upgrading Windows 8 to 8.1

Hi, I have a HP Envy 15-j059nr Quad Edition.

Audio was perfectly working until I updated my notebook from Windows 8 to Windows 8.1

Now, when I try doing calls through skype or google hangout, the other people in the calls get muted from time to time, I hear static. Also, they cannot hear me very well, I'm also muted or with static. The audio is really bad.

I've tried differet options of headset (that I have tested in other notebooks with success) or without headset, and the problem persists.

Any suggestions?

Thanks!