im am in the same boat, i was told by another user that the flutter is ok and wont hurt the turbo so i am guess the flutter is not same as the compressor surge, I have heard the same flutter on other car SR20 on SER had same flutter and was running a Greddy Type R bov and those bovs require more power(boost) to set them off so im guess that the flutter is ok. I have the SAME bov by the way
and i have mine T off also. well maybe someone will post some good news
good luck.