Can you provide a screenshot of the Status Page for the Android Player that is not displaying correctly? You can locate this by clicking the screen while Xibo for Android is running and selecting the Status option from the Action Bar.
Can you also confirm that there are no other Events scheduled to play on the Android Player with the issue? You can check this by selecting the Schedule option in your CMS and clicking on the box above the calendar named Select Displays.
Finally if you select the Displays option in your CMS, has the Display been Authorised? Also what does the Status icon for this Display show? It will be either a tick, cross or cloud.