I have an obi100 connected to googlevoice.
I can receive calls fine.
When I dial out I get no audio but the called party can hear me fine. This is a known problem since google stopped supporting xmpp.
A workaround is to call your own googlevoice phone number, enter 2, enter called phone number, enter #
Is is possible to use digimap to prepend this sequence to all phone numbers. If so could you give an example.