Most of today’s built-in sound cards are to some degree retaskable, which means that they can be used for more than one thing. That means you can turn your Mic jack into an extra Headphone jack, or why not make them both line outs, and connect them to your surround receiver?
I’ve known for a while that the kernel exposes an interface that makes it possible to retask your jacks, but almost no one seems to use it, or even know about it. So over the past few weeks I’ve been working (from time to time) with HDA-Jack-Retask, a small application that makes this interface easy to use.
Although primarily meant for power users, it focuses on simplicity: Just select your codec, then select which pins you want to override and what you want them to override to: Headphones, Line Out, Mic, Line In, and so on. There are buttons for trying it out right away, and for making your override the boot-time default. And of course, a button for removing all overrides in case things did not go as planned.
Consider it beta quality for now, and it’s one of those “won’t work for everyone” programs, but that’s mostly due to hardware and driver limitations.
It’s available for Ubuntu 11.10, and you can install it by adding ppa:diwic/hda and then installing the hda-jack-retask package. Start it by running “hda-jack-retask” in a terminal. Enjoy!