After 1.5 days of playing and careful observations, my main (and only) concern is the whistle. It definitely comes from the speaker, and volume of the whistle corresponds to volume of other sounds. Yesterday, when i was playing games, only the loudest volume was hearable. Few hours into gaming, i could also locate a sweet spot somewhere at 40% volume (the rest was still unhearable). Today all volumes worked, but the whistling did not stop, and i wouldn't lie if i said that it got louder. So, the state of speaker isn't stable, the fact that it got better by time is just dumb luck. Also, i tried to plug in old headphones, but it did not stop playing on the speaker and the headphones were silent. I can record a video of this to diagnose it further if needed. Cheers