Rattle noise under load

[turbofox84]

So I've been scratching my head over this one for a while. I get a really odd rattle noise when driving near the max psi I have adjusted for.(turned way down in an effort to not break anything before I fix this ~10psi) it almost sounds like a check valve bouncing back and fourth really quick or maybe the wastegate flapper. Car runs super smooth everywhere else including lower boost levels(around 3-7).
-I've ruled out detonation after pulling 6-8 degrees with no change in the noise.
-readjusted the wastegate linkage because I figured maybe it wasn't opening enough and exhuast back pressure was causing the flapper to vibrate under heavier boost.
-tried a bov instead of a bpv
-replaced the pcv check valve

Here's a little clip of the noise

You can hear it around :12 after I shift.

Any ideas are appreciated.

[Stinger]

Hard to tell while listening on my phone. Sort of sounds like an external gate that's vented to atmosphere opening?

[turbofox84]

its a turbonetics internal dual port wastegate, i have the top port run to the compressor outlet, and the bottom (closer to the arm) left open as its for an eletronic boost controller (or so ive read) guess i should try plugging that and see if it helps.

[Stinger]

If it's internal then it's not the noise.

Plugging the top port will result in unlimited boost.