An inventory of the technical side: how long each file is, what rate it was recorded at, how many channels it has, and whether those channels are actually different. A mono recording saved as stereo is twice the size for nothing, and it is far more common than anyone expects.
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Lists every file with its length, sample rate and channel count, and flags where those disagree with each other across the set.
A mono recording saved as a stereo file, with both channels carrying identical audio. It is far more common than anyone expects, because it is what happens when a mono microphone runs through a stereo interface and nobody changes the export setting. The file is twice the size it needs to be and sounds precisely the same folded down. On a course with fifty narration clips that is a real saving for no cost at all.
Not a fault in itself, since the authoring tool resamples everything on publish. It is a signal: files recorded at different rates almost always came from different sources, and that usually coincides with a change in room sound, microphone or voice between slides. Worth knowing before somebody else notices it.
Anything below 44.1 kHz is flagged, but for speech it is often a deliberate and sensible choice. Voice has very little content above 11 kHz, so 22.05 kHz halves the file at no audible cost. It is only worth a second look if nobody decided it.
It reports bit depth as the browser decodes it rather than as stored, because decoding normalises everything to floating point. For the original bit depth of a WAV, read the file header directly.