Reduce Bandwidth
From PhonePower Knowledge Base
If you find that your VoIP service is using to much of your available bandwidth you can lower the amount of bandwidth used by changing your audio codec. By default all accounts use the G711u audio codec. You can change this to G729a to use less bandwidth for your call audio at the trade off of reduced audio quality.
• Click Service Settings from your MyAccount menu.
• Click Bandwidth Control (Codec) from the Service Settings options.
• Select "G729a (Low Bandwidth)" from the drop down menu.
• Click Save Settings.
• When you change the bandwidth setting you MUST restart your phone adapter for the change to take effect.