2008 S550 Front End Clunk-Rattle

Hello all my 08 S550 has developed a very annoying consistent front end clunk / rattle. It doesn't consistently even on the slightest Road bumps including going over road reflectors. I thought it could possibly be the sway bar so I actually completely removed the end links and drove the car and there was absolutely no change the noise was still there so I'm 100% positive it is not the sway bar end links. I did replace the struts about a year-and-a-half ago with cheap after-market Chinese ones and although they are not leaking I suspect the noise might be coming from the internals of the strut. Has anybody had any experience similar to this with this noise or with aftermarket rebuilt struts? Any help would be greatly appreciated. I guess my next step is to just replace one of the struts with a new Arnott and see if the sound goes away. Thanks in advance.