I forgot to mention this after it was installed.

If you have an unused Media or Tape/MD button, put it to use by adding an Auxiliary Input Port to your system.

Comes with a Std. Mini Headphone connector which goes directly to any portable device you might have.

I run my XM portable from mine, wife pulls that plug and sticks on her GPS, or Ipod.

http://www.sylfex.com/products/AuxMod/Basic2sb.jpg

Got mine here:
http://www.sylfex.com/products/AuxMod/

Tested with the RX-8, Mazda6, Mazda5, Mazda3, Miata, MPV, Tribute and Mazda2.