Symptom:
QPS initiates the connection to DRA and immediately after CER-CEA happens the diameter stack gets an internal TIMEOUT event, terminates the connection and then initiates a new CER-CEA. Usually after the second CER-CEA the connection stays up and  DWR-DWA are successfully exchanged.

In some cases the DRA sends DRW immediately after CEA (almost the same millisecond) and because of that the stack is not yet in a state where it expects a message. After the third CER-CEA the stack seems able to handle the DWR.

Conditions:
The problem has been encountered when the diameter connection is initialized.