It appears OBITalk expects the Google Chat address to use the @Gmail.com domain versus @MyDomain.com.
The background is I've had Google hosting a domain for me with a number of user accounts on the domain for a couple of year now. Each user has a valid Google Email & Voice account. The @MyDomain.com GV accounts all function as expected being able to receive, forward and originate calls. The Google Chat address is
username@MyDomain.com and not
username@Gmail.com.
Google Voice numbers using a Google Chat address
username@MyDomain.com do not work. I moved that same Google Voice phone number to a standard Gmail account with a Google Chat address of
username@Gmail.com and it worked.
Based on limited testing it appears there is some type of incompatibility with OBITalk and Google Voice accounts with Google Chat addresses not using the
Gmail.com domain.
Please let me know if anyone has any questions.