Setting up my new Flirc with a Harmony 900 remote worked fine, especially after reading the Harmony sticky thread. But I consistently and reproducibly experience the problem that apparently Flirc emits multiple key events for a single key press on the remote.
Example: pressing 1 on the remote results in three to five 1 appearing on the screen (terminal, editor, etc) and of course also in XBMC. I also observe a very short delay between the first (desired) event and the subsequent (superfluous