no voice heard over the line channel ch=ipmB1C1 ErrorCode=0x5a04 -Out of Resource

Hi Team,

I wrote a SIP interface using HMP4.1 API to play a vox file. However, no voice is heard after the call was connected and answered. I checked the rtflog file and found below error was logged when the SIP interface was playing the vox file:

04/12/2017 17:42:49.730 24241 3991890752 libipm_ipvsc ERR1
CIPVscChannel ipmB1C1 --- ::OnReserveResource(): ch=ipmB1C1 ErrorCod
e=0x5a04 -Out of Resource

Any advice how to fix this? It might possible a configuration issue. I tried the SIP interface in office and it did play the vox file, but it failed to work after we registered it with another PABX server. I modified the RTP traffic base port and set it to be 32000 and still no voice can be hear from the other end.