Using Live 9.1.2 on Mavericks 10.9.2 on a MacMini 16Gb here with Spark 2 Build 334 as a VSTi plug.
Starting/playing with host sync works, but stopping leaves Spark in a mysterious "play" mode, showing active mixer audio output inside Spark on all channels in the mixer view but without any sound output to the host. Internal Play button on the Spark GUI is sometimes errateous blinking, sometimes not. Clicking the internal Stop button works the second or third time, not immediately. This happens every second start/stop sequence in Live and lasts a couple of seconds or forever, not determined.
Saving the active Live project or just closing Live during this mysterious behaviour crashes Live. This is no good...
Edit: The longer a sequence is playing in Live, the longer the mysterious audio output is shown in the mixer view and isn't stoppable via the internal Stop button. The pad icons are showing trigger activity in the mixer window and the main view when no real action is going on.
Edit 2, reproducable: Closing the Spark GUI in Live doesn't stop the mysterious audio output in the Spark mixer view on reopen. Sometimes the internal Play and Stop button are highlighted together, sometimes not. The CPU load indicator of Live is still showing activity even when Spark and other plugs are stopped, according to the audio activity in the Spark mixer view.
