Assertion: intro tone | /r/CapableOf | mute the audio
Facets:
Source sentences:
text: The "outro tone" was slightly lower at 2,475 Hz and signalled the release of the PTT button and muted the audio.
text: The "intro tone" was generated at 2,525 Hz and signaled the "key down" key-press of the PTT button and unmuted the audio.