[App_rpt-users] URI not found

Trying to help a friend get his Asterisk box up and running but having problems. His DMK Engineering URI is not being found. I can login and do lsusb and it's there, but asterisk app_rpt never finds it. Solid green led. I try to command radio active usb<node number> but when you check it says device not active. I wish I could try plugging in another URI but he is over 100 miles from my location. Any ideas or suggestions? Thanks Ed