Bug 478134

SUMMARY

When animation with audio, scrubbing (changing frames quickly via the timeline time ruler header) pushes multiple frames of audio which can block the program until the audio is processed. 

This is usually a minor issue, but becomes worse with (a) lower playback framerate and (b) lower playback speed.
Setting the animation to a low speed and framerate before scrubbing (with audio attached) will push tens of seconds of audio, causing Krita to slow down until it's all been played.

STEPS TO REPRODUCE
1. Open an animation
2. Attach some audio
3. Set low animation playback framerate.
4. Set low animation playback speed.
5. Scrub between frames on the timeline.

OBSERVED RESULT

Listen to a half minute of cow noises.

EXPECTED RESULT

We probably need to limit the rate of pushing audio based on the amount of time a single frame of audio takes to play (considering both anim framerate and speed).