Reads complex uint8 (re, im) from stdin, outputs UQ16 (unsigned fixed point, 16 fraction bits).
Requires rtlsdr (software and a receiver dongle) and sox (for audio output). For oneliner without server-client-architecture, drop the nc and just pipe the output of the demodulator to play.
Server:
rtl_sdr -f 91900000 -s 256000 - | go run fmdemod.go | nc -l 1337
Client:
nc localhost 1337 | play -t raw -r 256k -e unsigned -b 16 -c 1 -V1 -L -