Possibly compatible after changes
Disable SIP ALG or replace device
Netopia has SIP Passthrough “on” by default and will not work with VoIP services properly unless SIP ALG is disabled. (Or SIP ALG in newer models) In order to work with voice-over-IP, you must turn SIP Passthrough (SIP ALG) off. Note that not all Netopia routers may allow this change; if yours does not you must replace the device with a compatible router in order to use VOIP service.
The SIP ALG setting is not in the web gui. You have to telnet into the router.
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On the Netopia 4622xlt Telnet into the device. Use the arrow keys to highlight ‘quick menu’ and press “ctrl-n” that will bring you to the console.
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