yes. firmware could be a problem. did it work for 0.7.x for you? any chance you could test that without modemmanager? maybe try if the bits in https://edge.launchpad.net/~network-manager/+archive/ppa can still be used (downgrade and remove modemmanager).
if it works i need a log... start NetworkManager --no-daemon from console with NM_SERIAL_DEBUG=1 in env for that.
also you could just try and see if using CREG=1 does change anything.
yes. firmware could be a problem. did it work for 0.7.x for you? any chance you could test that without modemmanager? maybe try if the bits in https:/ /edge.launchpad .net/~network- manager/ +archive/ ppa can still be used (downgrade and remove modemmanager).
if it works i need a log... start NetworkManager --no-daemon from console with NM_SERIAL_DEBUG=1 in env for that.
also you could just try and see if using CREG=1 does change anything.