As far as I know it is only possible to reset the timer play function with a two way remote, i.e. Beolink 5000 or Beolink 7000. The only thing you can choose without the remote is whether the sound should be on or not (cannot rememember which button to press but I guess you have managed to do this already?).
Perhaps there is some kind of mastercode to reset the complete system but I guess that's a question for your dealer or local service technician then.
Wish you luck!