So here's my setup:
1. XBMC Live 10.1 running a minimal Ubuntu 10.04.3 (Lucid Lynx, I believe) connected via wifi 802.11n. All library is here, on internal drives. All drives functioning, networking connecting great and automatically via wicd-curses.
2. XBMC for Mac running on my Macbook Pro 2010 model, also connected to the same network via 802.11n, seemingly fully functioning.
UPNP sharing is enabled on the main media center. I connect, once, to it from my Macbook and add the source, no problem. If I close XBMC on my can and reopen it, and try to use that source again, it can't connect to it. And it never can again UNLESS I disable and re-enable the UPNP option on the main media center...then it appears as a possible source again.
Any idea why this is happening and how to fix it?