I have had similar problems with our historical household phone number after porting to Anveo and configured for the Obi202. The accompanying graphic shows the overwhelming number of short duration calls, mostly dead-air but some robo, relative to longer duration calls with a human on the calling end. This analysis was made on the Anveo SIP rather than Google Voice where the number of dead-air calls seems to be somewhat less frequent.
In a previous posting, one of the Obi/GV heros here suggested that the dead-air calls may be SIP scanners, but I never followed-up with an analysis to determine the nature of the calls.
On my to-do list is creation of a .csv "white list" file from my Outlook contacts to upload into Anveo's call treatment (call flow) system, but I have not gotten around to this yet. If I understand the concept, the dead-air calls will not even ring through to the Obi, which would be nice. That is unless the software initiating the call successfully spoofs caller ID to be one of the white list numbers, which sometimes happens.
