I am surprised that the OBI devices are configured by default as 10Mbps/Half-Duplex. I'm not sure what the reason for that is but it can't be that there are still network ports out there that use 10Mbps/Half-duplex.
Not sure also why there isn't an "auto negotiate" option either.
Moreover, there's no way to change the setting from the web interface (that I know of).
So here's how it's done via the phone:
1. Dial *** 0
2. Enter option 27 and press #
3. Press 1 to set a new value
4. Enter a value of 1 and press #
5. Press 1 to confirm/save
6. Hang up
Old news here had you done a seach.
Here is just one of many on that topic.
http://www.obitalk.com/forum/index.php?topic=2438.0
Joe Sica