Sound Wave assets are not always played when clicked in the Content Browser. After some testing, I think that this might be caused by attenuation.
It looks like all sounds played from the Content Browser are played from 0,0,0 scene coordinates. If attenuation falloff is small and our viewport camera is far from 0,0,0 sounds simply cannot be heard.
How to reproduce:
1 - Add wav file to project
2 - Create Sound Attenuation asset
3 - Set the Sound Attenuation asset like in the screenshot provided
4 - Open the Sound Wave and assign the Sound Attenuation asset to it
5 - Move your editor viewport camera far from 0,0,0 (further than Falloff Distance - 1050 cm)
6 - Click on the Sound Wave in the Content Browser to play it
Current Result: Sound does not play (in fact, it probably plays, but too far). If I move the editor viewport camera close to 0,0,0 I can hear the sound after playing it in the Content Browser.
Expected Result: Sounds played in the Content Browser should ignore the attenuation settings.