I am strongly convinced that the missing digital compass on the n900 is only a software problem and not a hardware problem. The earth-magnetic field influences the reception of fm-radio waves. If only anybody could help me to send a buffer of sound and to receive the same buffer of sound (without external antenna)!!! The utility "sox" available on maemo should be enough to analyse the deformation of the wave from transmitter to receiver. This should be enough to analyse the direction.