Comment 5 for bug 728161

Oh sorry for the confusing reply. I wrote that, then got busy with other stuff, and forgot to return to it. I have now made a dkms package for you to test, please try this:
1) Make sure you don't have alsa driver overrides installed (such as these: https://wiki.ubuntu.com/Audio/InstallingLinuxAlsaDriverModules )
2) Download and install http://people.canonical.com/~diwic/temp/alsa-hda-diwic-asus-g73jh-dkms_1.0.23.diwic_all.deb
3) Reboot and test.