BUG: Zap Focus to PiP doesn't work during media playback

[MrQuade]

So if you are watching a recording or media file, and activate PiP, a Live TV service will be displayed in the PiP window.

Press BLUE, and select "Zap Focus to Picture in Picture".

Pressing CH+ or CH- brings up the invalid keypress symbol on screen.

I'd expect CH+ and CH- to zap to zap the PiP display to the next or previous service in the the current bouquet.

This works properly if PiP is initially invoked from Live TV instead of from media file playback.