There seems to be a bug when several snapshots are involved at the same time with HTML API. Check http://chiptunegenerator.com/ click on start after loading, then press the button “build-up” and wait for it. In the middle of the build-up, you will hear the sound disappear (then comes back later with some scratches). The way it sounds makes you think of an engine low-level bug.
The bug occurs with a local web server, online, on both PC and mobile phone, but it doesn’t occur in FMOD Studio. The snapshots are triggered in a nested event. Nothing fancy in those (overriding) snapshots, only some faders down (different faders in each snapshot). It corresponds to the moment where 3 snapshots are playing simultaneously and one is released (bar 5 in the following picture).