911 One Way Audio

When calling 911 we can hear the operator but they cannot hear us. All other calls work fine on the PRI trunk. This is a CenturyLink circuit. CenturyLink suggests that we turn off “answer supervision”. I do not believe that this is even possible to do in Asterisk.

I think they are assuming you have an analogue line.

I don’t know how Asterisk handles early media on ISDN lines.