Depending on how many notes you’re playing, or the overall processing capability of your iPad / iPhone, the sound may be interrupted due to high CPU usage. If this occurs, go to iOS' Settings > "iWAVESTATION" > "Audio Latency”, and try changing the latency setting to "Safer".
The AfricanSunset patch seems to have a glitch. I use it frequently with the PC VST version. On an iPad3 with only the standalone iWavestation running, the patch "glitches" just a few seconds after play.