using_player event

I have added a second player and cannot get the using_player[cd1] or 2 to respond to the amp device command to switch inputs. The device file and maps are correct, as other events work and I can send the commands in the data stream send window without problems. Oddly enough, even if I put garbage in the using_player[cd1] command, starting the player from the device window will correctly set the amp input. This does not work when starting the cd 2 player from the same window. Any advice?