I know about the Audio plugin settings, but this problem still occurs. I think this is a big problem for the developers of Construct, becouse this indicator very much influences the ranking of games in Google Play. My game was in the top 20 in several categories for a long time, but after Google began to take into account the indicators of "bad behavior", my game fell to the bottom and downloads fell by 80%.
In the screenshot, you can see that the stuck AudioMix wake lock occurs at the beginning of the game session, perhaps when the game is loading and the engine starts to decode the sound, also many developers report that the problem appear when there are audio decoding threads. I tried to disable the "Preload of sound" in the project settings, but this does not affect the music so nothing has changed. Maybe if we disable also preload music, then this will change the situation, but of course these are my guesses.
I think if developers of the Corona, Gamesalad and Cocos2d engines reported about this problem, then you need to pay attention to it.