"Air Play Speakers not available. The speaker AppleTV is currently being used by someone else"

When I try to connect my iPad, I get the message "air play speakers not available. The speaker AppleTV is currently being used by someone else". This is then followed by "The operating could not be completed. I have tried "Reset" in the settings to no avail. I can get music to play on Apple Tv originating from my IPad and all other functions work.... Any suggestions would be appreciated. Thank you ...Ron