CMN-91
Installation and Operation Manual
Troubleshooting
© 2016 Imagine Communications Corp. Proprietary and Confidential.
Revision D | Page 150
Problem/Symptom
Possible Cause
Solution or Explanation
Waveform not locked when
External Reference (Ref:EXT)
is selected.
The video signal is too low in
amplitude or the sync edge is
too noisy.
Verify that the External Reference signal
is of sufficient amplitude.
EXT REF is selected but there is
no reference input, or the
External Reference is non
synchronous.
Select Internal Reference (INT REF)
and/or verify that the External
Reference signal is synchronous.
No sound on headphone
output.
The headphone volume is set
too low or the output is set to
"Mute" in the Audio Mapping
Matrix.
Adjust the headphone volume or select
the proper channel to be monitored in
the Audio Mapping Matrix.
Audio level reading is too
low.
The input reference level is not
correctly set.
Use the SETUP MENU to check the input
reference level setting.
Picture width is not correct.
The aspect ratio is not set
correctly.
Change aspect ratio in the setup menu.
No communications on
Ethernet port.
The IP address is incorrect.
Provide the correct IP address in setup
menu.
Incorrect Ethernet cable
For a direct connection, use a crossover
cable. For a network connction, use a
standard Ethernet cable.
If the problem still exists after troubleshooting the CMN-91, see CMN-91 Service and Support (on page
24) for further instructions.