Known Issues

  1. Many firmware versions that this router uses have DNS relay/proxy enabled by default, which causes DNS lookup timeouts on Polycom phones. That setting needs to be disabled to prevent intermittent or frequent phone registration failures.
  2. Therefore, we do not recommend this router since it's compatibility can be hit or miss, depending on what firmware version you are using.
  3. SIP ALG enabled by default.
  4. WAN Pings is disabled by default, which is an optional setting that is needed to allow the router to respond to our Call Quality Monitoring and Troubleshooting Ping Server.
  5. The WNDR3800CH is a version of the WNDR3800 with a custom firmware just for Charter Cable customers. 
    • Only Charter Cable can upgrade the firmware.
    • It does not allow disabling DNS proxy/relay, causing DNS lookup timeouts on Polycom phones.
    • It also has a known software issue that sets the MTU to 1482 or lower when it should be set to 1500. This causes strange phone and fax adapter issues, including registration, call/fax, and feature failures.

Temporary Resolution

Perform the changes in the article

Permanent Resolution

  1. Replace your Netgear router with a serviceable or recommended router if you do not have one already.
    • Intermedia cannot set up the new router for you, but your IT or the manufacturer of your new router can help you. 
    • They will need to move settings from the old to the new router to ensure your computers and other devices on the network work properly.