I tried this cut just now with both the B&W N802Ds and the Revel Studios and heard, of course, the flute along with the noise of AM's breath blowing across the hole in the mouthpiece and, also, his inspirations. At high levels, this was very noticeable but not annoying. I did not see any tweeter movement.

That you find such sounds, and others mentioned, unbearable or unpleasant may have to do with the balances you are getting from your system and room acoustics. This is treatable.

On the other hand, the asymmetric movement you describe for the tweeter in one of your S8s is suggestive of a defective driver since the tweeter should move, if at all discernibly, forward and back and without any other modes. If you reverse channels (at the preamp or amp) and the problem remains with that original S8, you need it serviced.

The cause could be almost anything, from amp instability to a leak from the MR/LF enclosure to random failure. Get it looked at.

Kal

Slight on-axis movement may be observed in some tweeters depending on their resonant frequency, the crossover feeding them and the signal content. I did not see any in my tweeters (I could feel it, though) but that's not here or there. It is the asymmetric movement of one of your tweeters that is of concern.

Kal