When using map monkey using a Garmin GPS II plus in NMEA mode, the GPS is detected and can pick up satellites etc, however the position is about 400m out - that is, at any given position, the position on the map is 400m south of what it should be. If travelling on a North/South Road, it shows the position on the road (still 400m south) though - East West position is fine.
Using the same software setup with another GPS (BU-303) it works fine (position correct).
Any ideas? *scratches head*