Correct, the music player running on a computer somewhere else on your network needs to support DLNA/uPNP/Open Home (this last one is an extension to uPnP AV) to use #3A.
You would need a virtual soundcard device like Devialet's AIR or Linn's Songcast to capture audio of other programs that normally output to a soundcard, and convert and stream this to something else. There's no direct support for this in the microRendu. However I do know about Jamcast which does this and converts data to DLNA/uPnP. I have never tried this program but in theory this would work. https://getjamcast.com
You would need a virtual soundcard device like Devialet's AIR or Linn's Songcast to capture audio of other programs that normally output to a soundcard, and convert and stream this to something else. There's no direct support for this in the microRendu. However I do know about Jamcast which does this and converts data to DLNA/uPnP. I have never tried this program but in theory this would work. https://getjamcast.com
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