I just installed PDIM P/N 22797218 HW=DB / SW=DD into my Camaro.
Sounded just fine (DB/DB unit would get occasional crackles when playing from my iPhone 3G).
There was about a 20 second pause when I first connected to my iPhone (indexing) and after that it was flawless.
I hope that is the last PDIM I ever need to install.