Thanks for the tip! On the PCATS website, it states that their tuner contains "built-in expansion capability for controlling two 12V relay outputs and interfacing four 12V switch inputs. There is also a connectivity option for future upgrade kits which could add further processing and I/O hardware..."

What exactly does that mean - ie. what exactly would these two things give me, particularly the "two 12V relay outputs" and the "four 12V switch inputs"?? What advantage to me are they, what would I use them for? Sorry, when it comes to electrical and audio components I'm quite a newbie...!

Also, are there any other 3rd-party FM tuners that will work with the Rio Car, or only the original one and the PCATS one?

Cheers!