Hey all, sorry Stevo96 for hijacking your thread, but I'm having some similar issue.
Mine is doing a random (cold or warm) starting noise just like marbles or something hitting metal inside the engine, and then a rattle noise after that at idle. I have no idea what is it but have read a lot here and there and all is giving me clues that it could be:
1) chain guide tensioner
2) chain guide rails
3) vanos needing a rebuild or at least new seals
4) a combination of all the above
I took a video to show you how it sounds, "unfortunately" it didn't do the marble start noise, just the later rattle as you can hear from this video:
http://youtu.be/rPKCOHDQMOQ
Forgot to mention, I have INPA with me and there are no codes related to the engine whatsoever.
Any ideas what it might be?
Thanks!