Pressing those two shortcuts to bring up Media and Playback on the menu don't work most of the time. I have seen them work occasionally, usually after items have been loaded in the playlist, but sometimes not even the. The shortcuts for all the other menu items seem to work consistently.
I've fixed this in git-master. Please let me know if it works for you.
Got the update from git-master and it does indeed look like you fixed it.
Marked as fixed consequently.