Pulled the air intake and the noise is definitely from the area of the ETA! Checked codes again just to make sure that they are not active (stayed cleared, and they were clear.

The butterfly (disk) area of the ETA is really dirty. Figured it may not get fully closed. Pressed gass pedal and the noise went away!

I'm hoping I'm dealing with an issue of dirt. Should I remove ETA and clean out of the car? Should I try to clean in place with the hot wire mass flow sensor removed? Has anyone used throttle body cleaner through the vent hose with the engine running (as per the throttle body cleaner directions)?

Paul