Hi all long time lurker 1st post. Great site.
I had a burnt exhaust valve and had the dealer fix under warranty. Just picked it up.
Now I get a high frequency vibration at engine speed that hits a resonance between 3k 4k enough to make it sound like your in a steel drum. It starts at Idle (faint) and continues all the way. Dealer says no problem.
I'm thinking balancer shaft is out of phase. Any suggestions.

Tia Shoe

 

yes, could be 180 out.

 

sounds like balance shaft.