Sorry, I didn't explain it very well. Caller ID works fine for the GV calls on line 2.
My current question only deals with line 1, the PSTN line. There is no caller ID on line 1, not because of any configuration issue, but because it's just not available on my PSTN line. However, with a standard phone connected to this line, I can tell a call from an on-campus phone as it rings normally, or an outside phone as it has 2 short rings. What would be great is if the Obi could recognize the 2 different ring cadences and either ring my IP phone distinctively so I can tell, or somehow display (perhaps via caller ID) whether the call is from on-campus or outside based on the ring that was detected. I like to know, because all on-campus calls are probably work-related and must be answered, while outside calls are likely phone spam.
Hopefully, that makes more sense what I'd like to do.
Right now, the only solutions I can think of are to 1) buy an external ringer box, or 2) Use a splitter and leave my old phone connected so I can hear its ring types.
A voicemail issue would not be good. I'll give that a try tomorrow.