Arrow Keys Skip Buttons

I am adjusting some the elements of the Amber skin music player. I notice now that I have mad some changes, some elements do not receive focus as I repeatedly click the left and right arrow keys on keyboard. Specifically, the Player buttons in MusicOSD.xml, A couple of them are skipped as I “tab” to the left with the left arrow key and another is skipped as I “tab” to the right with the right arrow key.

Any idea why this is happening? I don’t see a “tab” or “focus” order parameter.