Avalon 2005-12 :: 2GR-FEV6 Engine Tick At Startup?

I have a 2005 Avalon with a 2GR-FEV6 engine with approx. 130,000 miles on it that ticks or chatters for about 2 seconds at startup. The sound is coming from the #2 bank directly below & forward of the oil filler cap (forward most bank, right side). The sound is only present after the car has been sitting for 2-3 hours or more and relatively cool right before startup. There is no other drivability issues such as reduced performance, power or gas mileage. It's not throwing a fault code and the symptoms began within 5000 miles of changing to Royal Purple synthetic oil at 110,000 miles. I don't know if that is a coincidence or the reason for the ticking.

My initial thought was a faulty VVT-i oil control solenoid/valve but I pulled it out, put 12 volts to it and it worked fine. My second thought was a possible clogged VVT oil screen or filter. give me the possible symptoms of what a clogged screen would do? Would it cause the VVT-i actuator to lag just long enough to cause this noise since the oil needs to get through the screen to flow through the oil control valve to affect the operation of the VVT-i actuator and if so what is actually making the noise? It sounds like rocker arms slapping but just in that one spot.