I have the exact same problem. FMB920 set up on desk, running from a bench 12V power supply. The only things connected are red and black for power, no USB connected. The device pulls just under 6mA in deep sleep mode, confirmed using a calibrated multimeter and again on the ammeter on the bench power supply. The figures quoted on the Teltonika spec sheet are just not true, and this is a big problem for me as I wanted to use this tracker on an item of plant that is rarely used, so 6mA is far too high!