I have same problem than this video :

 

so the sound doesn't get louder or faster as the car revs?

 

No, you can only hear the sound when the car is idling.

 

i was gonna say lost motion assemblies, but that is frick loud to be those...

you checked your mounts and any of them bushing in the mounts? could be vibrating because of a worn mount. my thought is the low idle is creating that "noise" but the engine revving is matching the harmonics and vibration better so it eliminates the ticking OR just dampens the sound...


would help if you could get some video with your hood open and reving the engine from the throttle body and letting sit at idle for a bit for H-T to see and help diagnose