I seem to recall reading somewhere that the volume rocker on the LP5K does not work with the screen locked....
Meanwhile I emailed a Lotoo rep (got the email off the LPG forum) asking for the latest LP5K firmware, which turns out to be 6.1.0.8. Having no idea what features or bugs were addressed in this version since no notes were attached, I can't say what this upgrade provides but I can confirm the volume rocker works with the screen locked. I didn't test that with the previous version. By the way, upgrading is just so nice; put the file on your SD card and insert. Voila, it's done.
So with the new firmware version a long press advances or reverses songs (same as before), while a short press changes the volume. With multiple short presses you can make a significant volume adjustment......works like a charm.
I can't say enough about this little guy, I am really enjoying it. I also liked my N5 but found it a little too crisp for lack of a better term, although I will say in the week I used it, burn-in improved it no end.
The 5000 cradle is so practical and holds two micro SD cards for larger music libraries, so with the one in the player a total of three cards can be carried on the go, that's a nice touch. I truly feel with this firmware version, UI, battery life and accessories Lotoo has made a rock solid awesome player. I also really appreciate the fact the unit updates the music library without having to select that function. And pairing it with the JDS C5D has put it over the top for me, just an excellent combo.
My only small wish would be to enable the Function button with the screen locked. Overall I couldn't be happier.