Thanks for the replies guys.

No, I did not install a DSP amp as part of my nav retrofit. I was assuming that my car already has it and it is the "amp" that is mounted to the wall in the cargo area. I have an 07 Z4 M coupe that has the premium sound package.

I think I am going to get NavCoder so maybe that is something I can use to get my DSP function in the nav software functioning. As a last resort I'll bring my car to my dealer for programming.

Thanks again
Jim