I had this same ticking sound on my 07 when Idling; Applying little gas will make it go away and after letting off it comes back. Haven't had it for couple of months tho. I thought they were the lifters.
1. 2011 E82 135i DCT M-tec(Gone but not forgotten----> Totaled)
2. 2007 E90 335i JB Step(Gone but not forgotten---> grad school fund)