The Device ID number is used to differentiate between two identical units (such as two A-90s) when you want to send system exclusive messages to just one of them. To change the Device ID number, use the following procedure:
1. Double Click the Edit button so it flashes.
2. Type the number 1 on the keypad followed by ENTER.
3. CURSOR to Device ID and use the INC/DEC buttons to set the appropriate value.