FD1 issues; Stuck on Initializing, won't calibrate.. help please

My pretty new FD1 developed an issue. Worked fine until a few weeks ago. Turned it on and went to go through calibration process but it keeps on getting stuck with the remove display reading Initializing... and then nothing happens even if I leave it for ages. It also threw up a message saying Calibrate Vertical Compass or something along those lines but this may be because it won't let me calibrate it properly. Any help appreciated.