Side sound bar doesn't reflect some quiet sounds.

[N.W.L]

So while playing there are several times we're I hear sound effects but nothing is displayed on the side were values are normally show. Ex (like a fight going on and I hear it but the side bar doesn't react to this at all) is this intentionally or some odd edge case?

[R-26 Lightspeed]

I once reported exactly that as a bug for a specific machine's ambient sound, here was Kyzrati's reply :

Yeah this is normal behavior, and can happen with many machines in many situations. You can read more about how Audio Log behavior in that section of the manual. One of the basic behaviors you're probably seeing in this case is the fact that it doesn't list machines below 10% of their max volume. It is technically possible to hear things that don't appear there, especially with machines that have certain audio propagation behavior, or when you're playing with your system volume turned up higher.