Dial with moh stopped too soon

I am dialing to an external voip provider (sip) with option “m”. But the MOH stopped before the called partry answers the call. I hear complete silence until the called party answers. below is the log:

-- Executing [21189100@incoming:1] Wait("SIP/192.168.1.19-0856ebe8", "1") in new stack
-- Executing [21189100@incoming:2] Answer("SIP/192.168.1.19-0856ebe8", "") i                                    n new stack
-- Executing [21189100@incoming:3] Dial("SIP/192.168.1.19-0856ebe8", "SIP/                              297270519@202.0.175.62||m") in new stack
-- Called 297270519@202.0.175.62
-- Started music on hold, class 'default', on SIP/192.168.1.19-0856ebe8
-- Call on SIP/202.0.175.62-08604730 left from hold
-- Stopped music on hold on SIP/192.168.1.19-0856ebe8
-- SIP/202.0.175.62-08604730 is making progress passing it to SIP/192.168.1.                                    19-0856ebe8
-- Call on SIP/202.0.175.62-08604730 left from hold
-- SIP/202.0.175.62-08604730 answered SIP/192.168.1.19-0856ebe8
-- Packet2Packet bridging SIP/192.168.1.19-0856ebe8 and SIP/202.0.175.62-086                                    04730

pls kindly advise.