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Audio and video calls are dropping or only work one way when H.323 helper module is loaded

Resolve audio and video issues when the H.323 module is loaded.


If the H.323 helper module is loaded along with proper firewall rules or DNAT rules, and audio or video continues to drop or only works one way, application-level NAT might not be occurring.


  1. From the command line console type: system system_modules h323 unload
  2. Configure a transparent subnet gateway by following knowledge base article 123525.
  3. Start a video call from a Polycom device which is behind Sophos Firewall and check if it is functioning correctly.

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