I've been working through a similar issue with tech support. Following a reboot or power loss, the Obi110 would occasionally come up normally. More often, I found it with the Ethernet LED flickering, the phone LED off, and the device unreachable on the network. I'm still watching the beast, but after ~24 hours and a couple dozen power cycles I believe the following may have resolved the issue...
Reset the Obi to factory defaults
Set the Ethernet port to 100Mb FDX, if desired
Remove the device from the
obitalk.com portal and re-add it
Make any configuration changes from the expert option on the portal
This may work if all changes are done on the device as well, haven't tested that yet. In my case I believe it was using both the portal and local menus to make changes that caused the problem. It appears that this has also resolved issues with local changes reverting to defaults on reboot.