Change sound pitch without changing its length

One of the most frustrating things about working with sounds, I’ve found, is that changing the pitch will change the length of the audio clip, and quite noticeably. Bringing a sound an octave up cuts the length in half, and bringing it an octave down stretches the length by a factor of two.
I was making a MIDI composition kit and planned for it to be able to use real instrument sounds–but with this in the way, it’s not possible.

Perhaps this is a personal issue exclusive to me, but I find it silly that this hasn’t been fixed. Sounds have existed for some 6-7 years now, and we ought to have at least slightly more functionality for them.