Merr

I love my car I have a Sony Ericsson Xperia™ X10 phone with bluetooth connection to my Ford Edge sports 2011. Playing radio on Sirrus Radio in car... turn off the engine and open the door music in the car stops and my phone starts playing music. It is annoying and not always convienent. It is now doing it all the time. Any ideas???? Never used to do it.... just the last month. Await replies...