No RTP {very very urgent plz}

Hi all,

I was running my asterisk from one year. today i upgrade with once the caller is dialing the destination number caller can hear well real RBT from telecom and once called party pickup the phone the call became silence no voice both side.

Please try to help me ASAP 150 calls waiting couse of this issue.

When you upgraded, did you bounce the server? Also, did you update zaptel as well? All of these can play a part in getting it to work as before. Also, is this behind a firewall/nat, and if so, do you have the correct ports forwarded?