Can you please run bluez in debug at the time (sudo stop bluetooth, then sudo bluetoothd -d -n ), as well as NetworkManager in debug mode (see http://wiki.ubuntu.com/DebuggingNetworkManager) ?
Seems to me like there may be some further information in bluez debug logs that could point to an issue, if there is one, in bluetooth as to why the network is listed as down. ** Changed in: network-manager (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1165105 Title: bluetooth tether connection drops To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1165105/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs