hi all. my enquiry to Andre was put in this thread so I hope relevant. I have had an interesting few days playing with the Poweramp app and new eq app and addressing my volume issues, so thought might be nice to share in case helpful or if anyone can educate me.
Now mostly resolved my issues. Adjusted just about everything and got my S10+ sounding decent but not great hence the recent fiddling. Eq app eventually added Poweramp to known players so all working now. I discovered that the audio interface box that one can have on S10+ screen has sliders for bluetooth/wired headphones and another for app/media. This is reproduced when using samsung sound assistant but this has the added benefit of numbers beside the sliders for more accuracy. I find that purely accessing these boxes and putting the headphone slider to 140% (might be a clue here as to an increase in volume as 150% max rather than 100%?) significantly increases the volume.
I can then set Poweramp vol at 70/80% and my music is properly loud and punchy. Quite remarkable the difference and I have not seen this simple tweak/adjustment mentioned anywhere, which seems odd.
I'd love to have my bluetooth melomania buds, when pressing volume buttons, just adjust the bud volume and the phone vol buttons just adjust the phone/app volume, but this is a small gripe compared to the audio quality and loudness.