Out bound calling is not working in 1 Particular IVR number to CSR not connecting

Hi

I am new in freepbx but i learned something through forms, websits, etc

now i have one issue that we calling one US number to getting information initialy its start with IVR after pressing some option in dial pad its connect to CSR.

but this process not working through calling freepbx extension.

but same time i have configured my sip provider setting (which i have configured in freepbx trunk) in to my grandstream GPX1400 its working fine.

also i don't have this problem in some other numbers. i have cross checked with callcentric support they give some setting for trunk i configured but still i have problem.

while checking this issue i noticed one think while dialling freepbx extenstion through number the ivr answers welcome voice and some other voice in between next voice. but while calling callcentric account through my grandstrream phone it not playing that voice .

please help me to resolve this issue

thanks