Listening to the system output

[Limeth]

How would I create an input stream that reads data that is being played back by the default output device?
I can only get rust-portaudio to work with my microphone. The rest of the deviced either do not work or output noise.

List of devices:

0: HDA Intel PCH: ALC1150 Analog (hw:0,0)
1: HDA Intel PCH: ALC1150 Alt Analog (hw:0,2)
2: HDA NVidia: HDMI 0 (hw:1,3)
3: HDA NVidia: HDMI 1 (hw:1,7)
4: HDA NVidia: HDMI 2 (hw:1,8)
5: HDA NVidia: HDMI 3 (hw:1,9)
6: Cyborg F.R.E.Q.5 Gaming Headset: USB Audio (hw:2,0)
7: sysdefault
8: pulse
9: default
10: /dev/dsp

Output of uname -a:
Linux limebox 4.4.0-83-generic #106-Ubuntu SMP Mon Jun 26 17:54:43 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux