While playing a song, I wanted to browse, looking for a particular song. I selected an Artist, then an Album, after scrolling through all the songs on the album, I wanted to go back up to the album list for the same Artist. I pressed the Back button. Nothing happened. I pressed the Back button a second time. It went back up two levels, which was no surprise because I had pressed the Back button twice. So I went back down into the album list of songs. I pressed the Back button, and again, nothing happened. This time I turned the big knob and the display jumped back to the Album list and the cursor moved to the next album. Again, it took a second control action before the unit responded to both actions at the same time. I thought maybe it was a touchy button, so I repeated the test several times. Always the same behaviour. Am I doing something wrong? Or have I uncovered a bug?