When I stretch slots, notes start cutting off. It's not only audible. The voice count in Advanced View drops suddenly. Whoosh, off the cliff, in mid-note while I'm still holding the key.
It's most conspicuous when I am speeding or slowing attack sounds, like violin detaches.
For several seasons, I thought it was a RAM issue, because it behaves like the old days when only the header of the sample would play, and then the rest of the note was not fetched from the hard drive in time. Play, clip, silence.
In the last four months or so, I realized it was a stretch glitch, because as soon as I turn off the stretching slot by slot, the problem goes away.