Asterisk is blocking audio if ‘F’ flag is enabled in meetme with DTMF mode enabled as INFO for SIP channel.
If it is a bug in asterisk or something need to be enabled in sip.conf for the same.
Dialplan looks like
Exten => 100,1,MeetMe(100,dmF)
Robert V Chandran Tower, First Floor, West Wing,
#149, Velechery Tambaram Main Road, Pallikaranai, Chennai-100, INDIA.
Mob: +91-9176780669 | E-Mail: firstname.lastname@example.org
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