Mitel 3300 Technician's Handbook page 90

3300 ICP Technician's Handbook
6. If you assigned Music on Hold to an E&M port on the AMB (on a
controller with embedded analog) reboot the controller to start Music
on Hold operation. Or, if you assigned Music on Hold to a port on a
Universal ASU E&M card, reload the Analog Services Unit to start
Music on Hold operation.
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