MIDI-Note under the playhead

When programming a MIDI-Loop the note at the very beginning of the loop, i.e. 
where the playhead is located when the loop starts (with gridsnapping), won't 
get sent correctly and so won't get sounded. The terminal shows me:

"drop flushed event on the floor, time 0 < 3"

The next loop cycle then is processed correctly.

I'm using Ardour 3.0beta1a (built from revision ['11069'])