[VoiceOps] ATT Wireless Dropped Calls

[Eric Hiller]

This is a strange issue I just found out about, not sure how long it has
been happening. Apparently any ATT Wireless calls that come into our
system (an possibly just those that terminate into asterisk via sip(only
complaints so far)) are dropped. Our switch is connected to ATT Wireless
over ISUP/SS7 trunks and the calls are coming out as SIP. Asterisk gets a
SIP INVITE from the switch, then responds with a 100 Trying and a 200 OK,
The switch then sends an ACK and then a BYE. The ATT Wireless customer
just hears beep beep beep call lost.

Any ideas? It doesn't happen 100% of the time, but the vast majority. Also
a Wait(1) in asterisk before answering doesn't seem to make any
difference?

Thanks for any ideas!
-Eric