Grandstream box

1) Is it possible to save and restore the configuration of a Handytone 486 to a local file? So if I want to use one box, alternately between two providers, I load configuration A, then later configuration B, then configuration A again ... any way of doing that?

2) What are good settings for transmitting Fax through a 486, as regards Preferred Vocoder, and any other settings? If my faxes are transmitting at low baud rate, is that a VOIP provider problem, or a problem with the 486?

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