User's Manual

5.9.2.2. Audio Detection
Sensitivity Level: 0% to 100% (with 100% being the most sensitive)
Similar to motion detection, high sensitivity will trigger events more often than low sensitivity and produce more snapshots or videos.
However, over-sensitive events will fill up the storage very quickly. Even if you have unlimited storage space, large amount of files can become a
problem when you need to search through each of the files to find what you are really looking for. It may take some time for you to fine tune
the optimal sensitivity for your application.