I mainly listen to the music from my DX50 via the headphone out socket using Shure 215 in ear headphones. I have upgraded the firmware since 1.2.2 and never had an issue with any of them until 1.2.7
It installed fine, and the fixes were good, but the sound was many steps back. The previously posted 'Muddy' and 'Narrow' would adequately sum up my impression of it.
I tried it for 48 hours, but just couldn't get into it, so a quick step backwards and my musical goodness has returned.
So sorry iBasso, another vote on here against 1.2.7 - combine its features with an earlier soundstage and you may have a winner!