Audition results clip sibilence, but don't show on waveform

Whenever I apply multiband compression to a 32-bit voiceover file (edit view), I end up with good audio EXCEPT that the very high frequencies sound clipped. I always take the precaution to normalize to get my peaks below -3dB and the peaks never show as being above it after the process. Yet, the sound "splats" on high frequencies.

I'm using the on-board audio in conjunction with Matrox RTX2 card. Any ideas on where this is coming from? Is this just a limitation of Audition's multiband compression?