NDOF speed inversely proportional to distance to centre

Evening, lads.
The other day I got my hands on a 3D mouse and by a lucky coincidence it’s one that works in Blender, the 3DConnexion SpaceExplorer. It’s all good, feels very natural, this thick black knob in my hand (erm), but I did find one problem:

When I use it to control a camera in flight mode (Shift-F), then it slows down severely as I approach a point close to but not precisely at the centre of the world as indicated by the axes and grid. Conversely, it moves faster the farther away I am from that vague point/area.

Camera movement animated by automatic keyframing, grinds to a halt for no apparent reason

This is inconvenient because I was trying to record the movement of the camera. It doesn’t happen in free look, and strangely, it also doesn’t happen in Blender 2.63 (which I keep around for legacy reasons), so whatever it is must be somewhat recent-ish (on an evolutionary timescale 2.63 and 2.77 were released practically simultaneously) development that is to blame for this really quite annoying behaviour.

Anyone got anything? Anything that might help, I mean?