I have a S5 turbo which was rebuilt 50k ago and an Apexi BOV

This started about a week ago. I'm not sure if it's just temperature related or if the turbo is going bad.

When boosting around 8-10psi in the upper RPMS my BOV makes a chirp like the HKS BOV's do. I have the Apexi which normally just makes a WOOSH sound instead.

I did a bit of testing.
Doing 5psi doesn't make it chirp.
Instant high RPM boost(holding in vac at 5k then gunning it) causes the chirp.
Long high rpm boosts do it as well.

Normal 4-5k rpm half throttle shifts doesn't produce it.

I do remember that in thr 5k+ full boost runs that I get a bit of a whirring sound from the turbo.

Has anyone had somethign like this when their turbo was on it's way out?or when their Apex BOV wasn't working right?

Another possible cause I thought was that the air temps have risen lately(AZ heat already) so maybe somethign has changed there.
OR
The BOV is maybe not opening or shutting when it should so it acts as a whistle.

Thx