"the conference will now begin"

*️⃣ Asterisk sound 'confbridge-conf-begin.wav'
📦 From package 'asterisk-core-sounds'
🇦🇺 Spoken in Australian English

"if this greeting should be played indefinately"

*️⃣ Asterisk sound 'if-grtg-played-indefinately.wav'
📦 From package 'asterisk-extra-sounds'
🇬🇧 Spoken in British English

"...to mute, or unmute yourself. When you are muted you can not send audio to other participants. However you will still hear audio from other unmuted participants."

*️⃣ Asterisk sound 'confbridge-mute-extended.wav'
📦 From package 'asterisk-core-sounds'
🇦🇺 Spoken in Australian English

"to use the default attendant, just press pound"

*️⃣ Asterisk sound 'to-use-def-attendant.wav'
📦 From package 'asterisk-extra-sounds'
🇬🇧 Spoken in British English