I don't know what to make of that.
I didn't hear any distortion across the range actually and the pads are not bad.
If you have any doubts, you can safely go with 99Classics and be happy with them, but 99 Neo works pretty well.
99 Neo needs some break-in and the sound will change after a few hours. I don't recommend judging them before ~10 - ~30 hours have passed of them playing music on higher than volume. I also recommend using music instead of noise.
Meze recommends pink noise for 48 hours