Netgear FVS338.

Downgrade the firmware to version 3.0.4-19.
This version does not have SIP/ALG support.
This *should* allow you to register properly.

Note:
There is a Beta version of the firmware: 3.0.5-27.
This version has a SIP tab which allows you to turn off the SIP ALG.

NOTE: The information provided above is from another OnSIP customer offering these settings for other customers with a similar device. OnSIP does not sell nor monitor equipment and/or it’s firmware updates/etc. The settings of routers can change and are out of the control of OnSIP. For best results, reach out to the manufacturer directly.

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