In my network I have Polycom HDX8000 and IP phone registered to the same CUCM cluster.
When I make a call from Polycom to Cisco (or vice versa) and ip phone hangs up - Polycom after few seconds goes into restart.
Second case: when the call is established between cisco video endpoint and Polycom HDX there is a problem with one way audio (cisco is sending audio) - I have to enable EO for Polycom endpoint in CUCM configuration (which in official guide should be disabled). When EO is enabled in CUCM towards Polycom endpoint - everything works fine.
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It is always useful to include the currently used software version as issues experienced may already be addressed in a newer release.
This also allows yourself and others to check against current software release notes in order to verify if the setup you are testing is even supported.
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
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