trisQuel is still communicating with the ubuntu servers.
NTP servers are necessary to synchronize your desktop clock. Find a way to disable Internet synchronization on your desktop environment (something like "Time and Date" in a "Control Center").
there is guides for the mode-setting in USB to tell "ubuntu" that a given USB 4G modem is a modem and not a harddisk.
Follow them: Trisquel 8 is based on Ubuntu 16.04.
