My client has an Avaya Partner system. The Avaya tech told the client they could hook up an MP3 player to work as a Music On Hold system. The problem is that the input jack on the Avaya board appears to be smaller in diameter than the standard MP3 3.5 mm input jack. Does anyone know whether Avaya has a special sized (proprietary?) jack that needs to be used in order to plug in? If the size is unique, do you know the size and where I might be able to get a male to male connection cable? Please advise.