Problem with changing a speed of audio-

V.17 build 18: if I change the speed of any audio track, the sound is disappearing at all. I have to restart the program in order to hear the audio again. The main thing -- do not touch the speed again...

One more problem: sometimes sound disappearing if I change the pitch configuration of any track. Again, I have to reload the application.

Version 17 beta, build 23.