my rx6 is making a loud noise I can only describe as a "zing". It used to sound more like a whistle, but maybe it's because I have the windows down more now and can hear it more clearly. Is that just how ball bearing turbos sound?

 

update, seems to be most noticeable the first time I go WOT, less noticeable later.

 

sanity check: check the turbo, like shaft play and ensuring it's getting lubrication.

It may be a leak in your intake piping or interconnect.
It's hard to say without actually hearing it. However, on my T04B FC, I had a small leak in the intercooler piping interconnect and it would make a loud whining noise when I would boost to 10psi on the dyno.

J