Hi Leonardo Tadeu,
Before landing on to any conclusion i would like to get the answers for these questions.
1. What type of GW you use for outbound calls.
2. What type of connection (PRI, FXO or SIP Trunk) towards your ISP
3. What kind of response you get when you do outbound calls.
If possible pls do a test call and collect the below logs and post it.
debug voip ccapi inout
debug voip vtsp all
debug isdn q931 (If it's ISDN PRI)
debug ccsip messages (If your GW is SIP)
debug cch323 h225 (If your GW is H323)
debug cch323 h245 (If your GW is H323)
debug mgcp packets (If your GW is MGCP)
~ Kula