While streaming i would like to use my nexus 7 to play music, i don't want to have tons of stuff running in the background while streaming and with the tablet i could easily change the music without wasting time. So i believe this is technically possible, can anyone help me do thing. I believe i would have to have a two sided audio cable and setup something in the windows sound settings. Please help thank you!
You could technically have the tablet run a 3.5 to 3.5 male to male cable to the mic port on the PC and use a USB headset for your voice. Then use Virtual Audio Cable and combine the two mic streams, and pump the while thing out over twitch.
Edit: as the mic in is mono you would need a media player than can play stereo to mono on your tablet. Not a perfect solution but it covers the bases.
It would be way easier and a near negligible hit on performance to just run foobar in the background with the music coming from a separate drive so as not to impede the games load times.
There's a few different ways you could go about doing this.
The first and probably easiest way would be similar to Zibob's method. You could connect the tablet to an open 3.5mm input on your machine. Most have front and back inputs, and you can use them simultaneously if you already occupied one with a mic. However, instead of any 3rd party software like VAC, simply go into the input devices settings, tick 'Listen to this device' and all audio from the tablet will be added into your general/game audio. You can then mix the music and game audio in the windows volume mixer as it'll show up as another device.
Secondly, if your machine supports bluetooth audio from remote devices, you could also do that, which the overall layout would be similar to the first method. It would just eliminate a cable.
Thirdly, you could use a service like plug.dj, which is a music app that allows multiple people to play music from YouTube or Soundcloud in a turn based method. Just join your own DJ room on your tablet and computer and mute the tablet so that it doesn't play loudly in the room. However, plug.dj relies on flash at the moment, and is still working on a mobile app, so you'll have to use a browser like dolphin which still supports flash on android.
I would say that number 1 is your best option since it requires minimal setup and will be easier to setup for future occurrences.