[Trevally.]

When messages are sent to you they will come TDWs tab. But there is a % chance that it will not get to you (set in options)
When this message is sent using the campaign layer and it is classed as must be received - it will drop your TDC (set in options) and play a sound.
If TDW tab does not pick it up - the game one will.

So if you get messages and there is nothing there - check the captains messages.