Trust me I have used the search function and completely bamboozled myself, originally I was thinking swapping my Symphony II out for a 2nd hand RNS-e unit until I read I was wasting my time with th Mk.1 version and a Mk.II version is out of my budget. So I'm looking at adding a USB/Aux to my current unit for the time being but would appreciate some advice as to which on to fit? I've seen reference to a Dension unit but to be honest they seem expensive or what I need. I don't need bluetooth as the car has factory bluetooth module. I was thinking of something like a Connects2 or Anycar offering but advice from those who have either done this or are more technically minded than, which is 99% of people, would be appreciated?