I ask this as a first time user of a WBBB, my new HG Phoenix 20 is wonderful but during some 50* testing I get CBS. I have all the corners tight and the center not as tight and there doesn't seem to be any gaps. But with everything snugged up it seems that right where your butt pokes down on the left, the UQ loses loft from compression. So does this happen to you? What am I doing wrong?