[Riolist]

There's a total of 5 pushbuttons and 1 on-off switch on my player.

On the top the two switches are:

1. On the left is the on-off slide switch.
2. On the right is the volume pushbutton. This raises a volume screen in the now playing screen that enables the two lower front panel buttons to adjust the volume during playback. In other screens this button does nothing.

On the front panel there are 4 pushbuttons:

1. On the upper left is the main menu button, labeled 'esc' (strange). This allows you to drill down into the various primary menus and at the level when individual files or options are visible, to select them, and also to make selections in the sub-menus. A long press of this button returns to the main menu screen (my music, my video, etc)

2. On the upper right is the play/pause button. Besides activating play/pause during playback this button allows you to step back up through the main menu structure while in screens other than playback (the opposite of the drilling down of the 'esc' button). A long press will turn on/off the player in any screen.

3. On the lower left is the left directional button. in playback it is the rewind/previous track button and steps from bottom to top in the menus. It also adjusts the volume down in the now playing screen after the volume button on top has activated the volume screen.

4. On the the lower right is the right directional button. It does the same as the left button but in the opposite directions.

So that's it. As you can see, there's no process in these button functions to activate a sub-menu during ordinary menu navigation. They could have assigned that function to the volume button since it doesn't do anything in screens other than now playing, but they didn't.

I'm a little unclear about the capability of your player. Can you delete bookmarks using a sub-menu when you're in the Tag list screens?