i own an 02 wrx 5MT and recently i noticed a strange noise, sounding like a really breif whine that sounds like it is coming directly from the turbo (almost like a really really breif strange BOV). The sound only happens after about 3500rpm and at full boost when you let off the accelerator very quickly. As far as i can tell it is also only happening in 4th and 5th gear (i have a feeling it is happening in all gears but is only noticable in 4th and 5th). if anyone could give me a hand with what this could be and how to go about taking care of it i would really appreciate it. Thanks!