I also recently changed by Google password and received an automated recording from my Obi100 that said I couldn't use my Obi100 until I changed my Voice Service password at
obitalk.com to match my new Google Voice password. The problem was that when I went to the Obi Expert Configuration Menu, and then to the Voice Service submenu, and then to the SP1 Service submenu, and then to the SIP Credentials section, I was not able to input anything into the AuthPassword field.
The workaround that worked for me was to uncheck the OBITALK Settings box for the AuthPassword field, which then brought up an already checked Device Default box. I then unchecked the Device Default box, and by doing that the field became unlocked, allowing me to enter my new Google Voice password.
That wasn't the end of it, though. Once my new password was entered, I immediately received an alert message from Google Voice, "Someone just tried to sign in to your Google Account <ObiTalk email> from an app that doesn't meet modern security standards." The email included a link to Google Voice that talks about "less secure apps." At that Google Voice link,
https://support.google.com/accounts/answer/6010255, it explains how to change the Google Voice settings to allow "less secure apps" to access Google Voice. Once I changed that security setting in Google Voice, my Obi100 was able to make contact and now it works like it always did.
I presume that the firmware update allows for a more secure connection to Google Voice, but I always balk at updating firmware because of what can go wrong.