Engine noise, sounds like slight valve clatter after VSR Service on 2007 Lexus LS460

Bought ls460 in December 10, and engine ran very quietly, not tapping, smooth and quiet. Had Valve Spring Replacement (per recall) performed at Northside Lexus. Now when car idles it has a noticeable clatter sound that accelerates when the rpms increase. One salesman said "turn your radio up." It is very frustrating in that this is an expensive car...supposedly the best Lexus makes.
Any thoughts?

Asked by for the 2007 Lexus LS460
Do you mean VSC (Vehicle Stability Control service) or the valve spring recall work. If the noise was not present prior to the work I would protest more loudly, call Lexus North America Customer Service if you have to.
Thank you Patrick,
Yes, it was after they did the valve spring replacement recall work. Do you have any idea what this may be?