I have a ‚master‘ max2play with a hifiberry amp and wanted a line input too.
It was dead simple…
I had max2play in a working setup, as my main squeezebox server which serves 4 other pi’s. This one was setup with the hifiberry amp. I bought a Behringer U-Control UCA202 USB Audio Interface 2-in/2-out (externe USB Soundkarte)
– activated the waveinput plugin in lms.
– connected the UCA202 with a chromecast audio connected to it.
– ssh into the box (pi/max2play)
– arecord -l to find the sound card number. (1 in my case).
– sudo reboot
Had to change the hifiberry amp from „-o hw:1 -V Digital -C 5″ to „-o hw:2 -V Digital -C 5″. Was easy peasy because max2play told me to do so 🙂
– in lms I added a favorite: url „wavin:plughw:1“ where the final 1 is the number found with arecord -l
Selected the favorite and casted to it, done.
With my previous fiddling with icecast/darkice as a streamserver it worked too: downsides were that I had to use another raspberry pi and I had to set the volume almost to max. If you switch to another source that’s enough to scare the hell out of my home rabbit 🙂