use OpenSips as SIP PROXY, have some problems when call

log_level=3
sip_warning=0
log_stderror=no
log_facility=LOG_LOCAL0
#log_name="opensips"
debug_mode=no
children=4
dns_try_ipv6=no
auto_aliases=no
listen=udp:192.168.0.138:5565 as 36.104.147.190:5565
advertised_address="36.104.147.190"
advertised_port=5565
alias="36.104.147.190"
mpath="/usr/local//lib64/opensips/modules/"
db_default_url="mysql://opensips:opensips.pwd@dbserver:3306/opensips"

loadmodule "db_mysql.so"
loadmodule "signaling.so"
loadmodule "sl.so"
loadmodule "tm.so"
loadmodule "rr.so"
loadmodule "uri.so"
loadmodule "dialog.so"
loadmodule "maxfwd.so"
loadmodule "textops.so"
loadmodule "mi_fifo.so"
loadmodule "dispatcher.so"
loadmodule "load_balancer.so"
loadmodule "sipmsgops.so"
loadmodule "proto_udp.so"
loadmodule "path.so"
loadmodule "cachedb_local.so"
loadmodule "usrloc.so"
modparam("usrloc", "nat_bflag", "NAT")
modparam("usrloc", "db_mode",   2)
loadmodule "nathelper.so"
modparam("nathelper", "natping_interval", 10)
modparam("nathelper", "ping_nated_only", 1)
modparam("nathelper", "sipping_bflag", "SIP_PING_FLAG")
modparam("nathelper", "sipping_from", "sip:pinger@127.0.0.1") #CUSTOMIZE ME
modparam("nathelper", "received_avp", "$avp(received_nh)")
loadmodule "nat_traversal.so"
loadmodule "uac_redirect.so"

modparam("mi_fifo", "fifo_name", "/tmp/opensips_fifo")
modparam("dialog", "db_mode", 1)
#modparam("dialog", "db_url", "mysql://opensips:opensips.pwd@dbserver:3306/opensips") 
modparam("rr", "enable_double_rr", 1)
modparam("rr", "append_fromtag", 1)
modparam("tm", "fr_timer", 2)

#modparam("dispatcher", "db_url", "mysql://opensips:opensips.pwd@dbserver:3306/opensips")
modparam("dispatcher", "ds_ping_method", "OPTIONS")
modparam("dispatcher", "ds_ping_interval", 5)
modparam("dispatcher", "ds_probing_threshhold", 2)
modparam("dispatcher", "ds_probing_mode", 1)

#modparam("load_balancer", "db_url", "mysql://opensips:opensips.pwd@dbserver:3306/opensips")
modparam("load_balancer", "probing_method", "OPTIONS")
modparam("load_balancer", "probing_interval", 5)

loadmodule "rtpproxy.so"
modparam("rtpproxy", "rtpproxy_sock", "udp:127.0.0.1:7890") # CUSTOMIZE ME

route{ 
    force_rport();

    if (nat_uac_test("23")) {
        if (is_method("REGISTER")) {
            fix_nated_register();
            setbflag(NAT);
        }else {
            fix_nated_contact();
            setflag(NAT);
        }
    }

    if (!mf_process_maxfwd_header("10")) {
        sl_send_reply("483","Too Many Hops");
        exit;
    }  

    if (has_totag()) {
        # sequential request withing a dialog should
        # take the path determined by record-routing
        if (loose_route()) {             
               if (is_method("INVITE")) {
                # even if in most of the cases is useless, do RR for
                # re-INVITEs alos, as some buggy clients do change route set
                # during the dialog.
                record_route();
            }
            route(relay);
        } else {
            if ( is_method("ACK") ) {
                if ( t_check_trans() ) {
                    # non loose-route, but stateful ACK; must be an ACK after
                    # a 487 or e.g. 404 from upstream server
                    t_relay();
                    exit;
                } else {
                    # ACK without matching transaction ->
                    # ignore and discard
                    exit;
                }
            }
            sl_send_reply("404","Not here");
        }
        if (check_route_param("nat=yes")) 
            setflag(NAT);
        exit;
    } 

    if (ds_is_in_list("$si", "", "1"))
    {
        route(relay);
        exit;
    } 

    # check if the clients are using WebSockets or WebSocketSecure

    # CANCEL processing
    if (is_method("CANCEL"))
    {
        if (t_check_trans())
            t_relay();
        exit;
    }

    t_check_trans();

     # If the request is a register we will pass it along but we need
    # to add the path header (along with the received IP/port info)
    if ( is_method("REGISTER"))
    { 
        if(isflagset(SRC_WS)){
            # if we fail to add the path header then dont let it
            # register because it will cause issues later..
            if (!add_path_received())
            {
                xlog("L_ERR", "$ci|log|unable to add path");

                sl_send_reply("503", "Internal path befuddlement");

                xlog("L_INFO", "$ci|end|cleaned up call id from cache");

                exit;
            }
            xlog("L_INFO", "$ci|log|added path");
        }

        if (isflagset(SRC_WS)){
            fix_nated_register();
            setbflag(DST_WS);
        } 
    }

    # preloaded route checking
    if (loose_route()) {
        xlog("L_ERR",
        "Attempt to route with preloaded Route's [$fu/$tu/$ru/$ci]");
        if (!is_method("ACK"))
            sl_send_reply("403","Preload Route denied");
        exit;
    }

    # record routing
    if (!is_method("REGISTER|MESSAGE"))
        record_route();

    if (!is_myself("$rd")) {
        append_hf("P-hint: outbound\r\n");
        route(relay);
    }
    # requests for my domain

    if (is_method("PUBLISH|SUBSCRIBE"))
    {
        sl_send_reply("503", "Service Unavailable");
        exit;
    }

    if (is_method("REGISTER") )
    {    
        if (!ds_select_dst("1", "0")) {
                send_reply("503","Service Unavailable");
                exit;
        } 
        if (isflagset(NAT)) {
            setbflag(SIP_PING_FLAG);
        }

    }
    else if (is_method("INVITE")) {
        if (!load_balance("1","pstn")) {
            send_reply("503","Service Unavailable");
            exit;
        }

    } 
    if (isbflagset(NAT)) setflag(NAT);        
    route(relay);
}

route[relay] {

    if (is_method("INVITE")) {
        if (isflagset(NAT)) {
            rtpproxy_offer("ro");
        }
        t_on_branch("per_branch_ops");
        t_on_reply("handle_nat");
        t_on_failure("missed_call");
    }
    if (isflagset(NAT)) {
        add_rr_param(";nat=yes");
    }
    if (!t_relay()) {
        send_reply("500","Internal Error");
    };
    exit;
}

branch_route[per_branch_ops] {
    xlog("new branch at $ru\n");
}

onreply_route[handle_nat] { 
    if (nat_uac_test("1"))
        fix_nated_contact();
    if ( isflagset(NAT) && has_body("application/sdp"))
        rtpproxy_answer("ro");
    xlog("incoming reply\n");
}

failure_route[missed_call] {
    if (t_was_cancelled()) {
        exit;
    } 
}

local_route 
{    
     if (is_method("BYE") ) 
     {
        # acc_log_request("internally generated BYE");
     }
}

OpenSIPS / opensips

use OpenSips as SIP PROXY, have some problems when call #3101