what if audio comes from a radio transmitter, somewhere is a radio sign with 101,4 and you adjust your radio to 101,4 so you can hear it. transmitters could have a smal range and focusing multiple thinks like
(example- not related to something)
Bord AI: 101,2
Bord radio: 99,3
Cpt. Spech 104,2
Emergency: 505,0
used recievers (nedo tool) have different quallitys and ca recieve 1 to 8 frequencys (for example) there is no air in space but radio stuff could be a thing