The Hagerman HagUSB is a great converter and one that I recommend.
Note: You'll need to connect the HagUSB directly to your Mac. The AirPort Express has an USB port, but it does not transmit audio. It's used as a print server for USB printers.
Note: You'll need to connect the HagUSB directly to your Mac. The AirPort Express has an USB port, but it does not transmit audio. It's used as a print server for USB printers.