why do I have bad interference with my bluetooth and Iphone? Obnoxious noise

What is your question?

I have upgraded the phone several times and there seems to be poor connectivity between existing bluetooth in 2006 lexus and the newer technology. Very often I get this obnoxious noise when I try to use my newer technology cell phone through the 2006 bluetooth that came with the car? Is there an upgrade or remedy for this? I have spoken to ATT, Apple and Lexus to no avail. HELP