When using samples in a (VoiceAttack action-based)loop, for example as an alarm or even background system noise, there is a noticeable gap between the sample ending, and starting again.
The most likely solution I can see to this would be to have the built-in audio system(s) loop a file natively, if it is possible.
Such an action would have to run asynchronously(and be mutually exclusive with "Wait until sound completes before continuing command"), so would currently only end when the "Stop Sounds" action, or the "This completes all other currently-playing sound" option are called.
If there is a way to make a specific sound loop stop without stopping all other sounds/loops, that would of course be handy.
A "Loop sound while" action, for example, which would monitor a variable the same way a regular while loop does; Though that would likely necessitate an additional watchdog loop per looping sound to monitor said variable, unless the engine raises an event when the loop comes around.
On the other hand, an external loop could possibly allow for a "fade out when loop ends" option that can stop the sound immediately mid-playback(very useful for samples longer than a few seconds).