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What is "double key press"
In this case we'll start off with a description of the symptoms of double key presses:
For example: You press the down arrow once on your remote control and onscreen the selection moves down twice (rather than once)
This is an example of one press and flirc sending two.
Why is this happening
This happens because Flirc might actually think the user pressed two buttons because the infrared packets from the remote control are so far apart.
Increasing the interkey delay will tell flirc to wait longer before deciding the button was let go.
How to fix it
Go to the advanced section of the GUI
Now, we will want to change the inter-key delay. If it's currently at zero, increase it. Increasing this value should help.