Anyone got SMS to be read over Car Stereo?

[Johnny Cakes1]

I was able to get SMS to be read over bluetooth just like Windows phones does, using this app
SMS, My car and me..

BUT... it will only play over my stereo if its on the Bluetooth input, and it won't interrupt the Radio, CD, or SAT inputs (which i listen to most.) like a regular phone call does..

Wondering if anyone else has tried this..

thanks