Crashing on Input.IsDown(69) C#

[Lanum]

I have code that checking is button "E" pressed but client crashing

new Timer(OnKeyPress, null, 1000, 1000);
private void OnKeyPress(object state)
{
	if (Input.IsDown(69)) // 69 = E
    {
    	Chat.Output("E pressed");
    }
}