Orage alarm did not occur

[Stuart McGraw]

I am a Gnome3 refuge who wishes he'd discovered Xfce
a long time ago.  However, I am having a problem with
Orage.

For some time I have had the suspicion that the alarm 
feature of Orage was not going off when it was scheduled 
to.  But when I've tried to test it, it's worked fine.

I just had a case where there was definitely a problem.
In mid-January I created a dentist appointment for Feb 8
at 9am.  In the Alarm tab, I had set the "Alarm Time" to
"2 days, 0 hours, 0 mins before start".  I expected the
alarm to sound on Feb 6 at 9am.  That never happened.
But today (afternoon, Feb 7) when I opened the Orage applet
to set an unrelated appointment, the dentist appointment
popped up and the alarm sound played.

Is this a known problem?  Or is there something I may
have done wrong when setting up the event?