Most any John Cage will fit in here, but the antithesis of silence is a piece called "Solo for Voice 22, Theatre with Electronics (from Songbooks, 1970)". It is a duet of sorts that involves electronically filtered sounds of breathing and sniffing. It actually has a written score that dictates when and where motifs of irregular vs. regular breathing through mouth and/or nose are to be administered. It is hard to imagine that it was written with a clear mind.
Srangest ,most out there sounding music
Whats really thrown you for a loop!