Hi, I have the same problem with FM36M1, with 1.12.02 firmware. Seems it was ok with older versions.
The coordinates and speed is corrupted for a short time, eg.
Speed 144, location 27.70000,1.033333, but should be Speed 110, location -27.700000, 153.208841 (correct location).
The Latitude seems always to be positive (when in error), where Australia should be negative (-27.xxxxx) and Longitude shows positive 1.xxxx (when in error) and should be positive 153.xxxxx
Happens regularly.
Thanks