# h324SetAudioTxPayloadID

Sets the audio RTP payload ID in the transmit direction.

#### Prototype

DWORD h324SetAudioTxPayloadID ( MSPHD msphd, WORD payloadID)

Argument | Description
msphd | MSPP handle associated with the MUX endpoint.
payloadID | Audio RTP payload ID.

#### Return values

Return value | Description
SUCCESS |
CTAERR_NOT_FOUND | Provided msphd does not map to a current audio pass-through channel. Either h324Start was not called, h324Stop was called, or the wrong handle was passed by the application.
H324ERR_INTERNAL_ERROR | Internal error in the 3G-324M Middleware.
H324ERR_MUTEX_LOCK_FAILED | Internal error trying to lock mutex.
H324ERR_NOT_INITIALIZED | h324Initialize was not called first.

#### Example

{
DWORD result;
WORD payloadID;
payloadID = 100; // Set AudioRTP payload ID to 100
result = h324SetAudioTxPayloadID(GwConfig[0].MuxEp.hd, payloadID);
if (result != SUCCESS)
printf("ERROR: h324SetAudioTxPayloadID () failed.\n");
}