Dead air for only specific dial patterns on outbound calls

Had our FreePBX server running for a couple of years now with no real issues. For some reason in the last few days, when we dial out to numbers with 1300 XXX XXX, or even just 13 XX XX, we get dead air. The call appears to answer, but I can’t hear anything.

I get the following in the asterisk logs.

[2019-09-26 11:56:43] NOTICE[2098] chan_sip.c: Disconnecting call ‘SIP/0282432310-00000260’ for lack of RTP activity in 31 seconds

The strange thing is calls to any other number format work just fine. Not sure what to look at. I’ve tried deleted and recreating the outbound route for the problem numbers but that didn’t help. Also checked the firewall to confirm that RTP 10000-20000 is allowed.

Any thoughts on where I should look next?

interesting follow up to this, the only 1300 number I can successfully dial is my voip providers, which makes me think perhaps a fault on their end?

VoIP provider confirmed an extra IP required through firewall, so this is now resolved.

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.