Rorschach Audio and the Cemetery of Sound - Electronic Voice Phenomena and Sonic Archives
irrespective of their original broadcast frequencies, a huge range of electronic transmissions share a tendency to demodulate onto (and become audible though) the amplifying circuits of radio receivers and tape recorders etc, producing what are often referred to by engineers as "stray" voices
Cocteau's film suggests that coded radio messages "inspired by the BBC broadcasts of the occupation" were transmitted from the metaphysical underworld - Orpheus asks Heurtebise "Where could they be coming from? No other station broadcasts them. I feel certain they are addressed to me personally".