I recently acquired an Alpine CM5908 for my 1989 M3 from a Canadian M3 owner who duly gave me the 5 digit code to unlock the radio. Having gone through the usual protocol many times (waiting an hour or more, disconnecting the battery, etc.) the radio still won't take the code. Could there be a problem because the radio is presumably from a Canadian car and mine is a US spec car? One reason I suspect there is a mismatch is that the serial number stamped on the radio box is not even accessible to US dealers. Thoughts anyone? Thanks, Jeff
