Originally Posted by aron7awol
After further research, I think the Behringer U-PHORIA UMC1820
might work, as long as it can accept 6 stereo inputs and I can control them through an API. Does anyone know if it will meet my needs?
That won't really do what you want it to - that's for getting audio in/out of a computer for recording.
Edit: you don't really want to take the audio into the computer, you want an outboard device that processes the audio, and allows you to control it from the computer.
You said above you wanted to do surround sound - if that's a requirement, it gets much tougher - probably best to just use a receiver and switch inputs at that point.
Switching the sources and mixing the sources would take different hardware (well, switching would be cheaper hardware). If you're just looking to switch, check out some extron switchers on eBay. Most also switch video, but you can just not use that. Look for an older composite video or RGBHV switcher (although any video switcher with analog audio would work).
The newer ones come with network ports - you essentially telnet in and send specific commands to switch inputs. The older, cheaper ones have serial ports, but they work the same way. Just run a cable to the serial port of your PC, and send the commands to the com port.
If you're looking to mix the sources (so you can hear multiple ones at once, or program a nice crossfade between two boxes when you switch), you're going to need something more powerful, best bet would be a pro audio DSP. There are several options here, but your best bet will probably be a used ClearOne, Getner, or Biamp Nexia unit. Just be sure it has 12 inputs for all your sources. Depending on the model you get, there may be some programming/configuring required, but I'm guessing you could handle that, maybe with a little direction. Controlling it is very similar to the switch above - either telnet in or use a serial port. Since these units are very powerful (can do mixing, gating, eq, and a host of other features), the control is a slightly more difficult protocol, but it's not bad and probably well documented.
If your computer doesn't have a serial port, there are USB to serial adapters, with varying degrees of reliability, and also IP serial port servers, which you basically just telnet into, and it connects to the serial port on the device.