Whining/Screaming

[ZakS13]

have a CA18DET, all stock except everything listed below. I've been driving it the past month and its been running/driving/boosting fine. Started it up today, took my friend home, no problems.. a few minutes later, i noticed that when i would start hitting boost, there was this whinning/screaming noise like a supercharger or something? oil level, pressure, and temperature are all good. turning the elec. fan on/off didn't help, and it does it primarely in gear, and a little bit at around 6-7k in neutral. any ideas? after searching some i think it may be the turbo-manifold gasket?

also, no power steering or A/C, and does flucuate with boost. very minimal shaft play, no boost/vac leaks, and no BOV (like factory).