URL Networks

VoIP Issues with Registration and Quality

You are here: Help Troubleshooting VoIP Issues with Registration and Quality


Unable to Register

  1. Try is to try changing your local SIP port on the phone to something unique on the network. For instance set the first phone’s port to be 5000, the second to be 5001 etc.
  2. Often ADSL routers have a feature enabled called “SIP ALG”, we find that it is best to make sure you disable this feature. For help on disabling the SIP ALG feature you search Google for your router model and disable SIP ALG.

Calls Disconnect for no Reason

  1. Another tip is to try changing your local SIP port on your PABX to something unique on the network. e.g. 5001
  2. Often ADSL routers have a feature enabled called “SIP ALG”, we find that it is best to make sure you disable this feature. For help on disabling the SIP ALG feature you search Google for your router model and disable SIP ALG.

Incoming Call Rings, unable to pickup

  1. Another tip is to try changing your local SIP port on your PABX to something unique on the network. e.g. 5001
  2. Often ADSL routers have a feature enabled called “SIP ALG”, we find that it is best to make sure you disable this feature. For help on disabling the SIP ALG feature you search Google for your router model and disable SIP ALG.
  3. Sometimes some routers have a DOS protection enabled, often when enabled the router will confuse a genuine calls with a DOS attack and block the packets at the router. It is recommended you try using the service with this feature turned off on your router.

Calls Quality

  1. A lot of call quality issues can be solved by making sure your device is using the correct codec, if you check the settings of your device make sure that G729 is listed as the preferred codec.
  2. If you have several people using your Internet connection you may be suffering from congestion, there are two ways to address this:
    1. Use a router that supports QoS such as the Mikrotik range, visit our website for more information and we can assist you with a QoS router - http://www.url.net.au
    2. Consider installing a dedicated ADSL line for your VoIP devices to use. If you require a dedicated internet line for your VoIP service please visit our website - http://www.url.net.au