Sounds like the music path is off. Try going to the File menu and locate moved or missing files. Typically the graying out and moving to the next file signifies that the software doesnt find the music in the list.
Im fully aware. Im sure there are portable systems that are excellent. A cell phone however isnt one of them. Obviously these manufacturers make them with a primary goal, making phone calls and texting, over audio.
The review I read was on the OS and hardware. It wasnt an audio test. Lets be honest. Who is using $4-$500+ headphones with a cell phone? Headphones in that price category deserve a dedicated home setup, not a portable setup.