On my 2016 Macbook (using a Magic Keyboard) I often have a problem entering lyrics in Dorico, where I’ll arrive at a syllable, type a word, and the first one or two letters will disappear. I’m fairly sure that it’s not simply that I’m typing too early – I see the text appear and then disappear. I think what happens is the first letter(s) will appear, and then disappear, and then the rest of the word will appear as I type it. As opposed to the entire word showing up, and then the first letter(s) disappearing. I can’t guarantee it’s always one way or the other, though.