When I try to adjust audio volume, using the up or down volume control buttons, while listening to another app (Beyond Pod), the notification area flashes briefly with "Media...<name of bluetooth device>", then it shows the word "Poweramp" above a square icon with quarter-circles in its lower left corner and a horizontal line with a circle, indicating, apparently, the volume PA wants. The audio volume remains unchanged, even though the PA app has been closed; it is not playing music, but simply won't let me change the other app's volume.
I've tried various settings: enabling/disabl