Hi. I feel your frustration...this is my third post on your thread. It's a bit ridiculous. It would be perfect if they just sorted this. As you said it's not like landing a probe on a comet. If we all keep posting will they notice us...the headphone gang.
It's not the device problem. Works loud and great using Poweramp music player and Google music. Spotify so low. And this is 2018 may 6 . Low . If it was my device why would it be very loud on Google music and Poweramp? Smart one? Let me know