Well the first thing which is strange that you jump with your mouse from Bar 3 to 6.
Some sounds, even if they are drones, still have natural decay times set up. I don’t know Alchemy, however in most synth-patches you can program how long the patch is playing in bars – so how many bars you sound is decaying, if that makes sense. If you take 10 other patches, and everyone has a “cut-off” thing going on, then sometimes is really wrong. Sometimes what happens as well, if you have a MIDI-note on the exact 1.00 Bar/Timecode, that the sound is not playing properly. Because of this, sometimes I start my compositions not on the first Bar in the DAW but somewhere on the middle, like 33 or 65, so I have plenty of room in the front, as well in the case, if I need to put sometimes in front…you never know!