Thanks. As an update, I think I have everything working now. I couldn't get the automatic setup on the Jabra to work so I called them and they walked me through it manually, but as a result I don't think it configured the audio the way it does if you call in the number. There is a bit of quality loss between the Obiphone and the headset. My mom said that when I used just the phone itself sounded extremely crisp, "like the way phones sounded in the old days," so that is great. When I had the headset on, it was fine, and we could both hear each other, but the call quality was just average.
It's a little disappointing that there would be this difference, I had assumed that with a $200 headset this wouldn't be a problem. I'm not sure if it's worth it for me to rock the boat as I am going to be logging lots of overtime for work in the next few weeks so I may as well just move on, but based on my experience I might choose a different headset.