Hi @sj1, note 4 is present in the audio track for playing activity #5, but it doesn’t appear in every measure. If you just listen to the strumming guitar and the bass outlining the reggae rhythm, I’m not sure that note 4 ever appears in these two parts. So in some measures, note 4 is absent and so you could imagine these chords as 2- and 1, since we’re only hearing the triads of the chords. But at the end of each line, you’ll hear a low melody line made up of the notes 2, 3, 4, 3, and in this moment the harmony is unequivocally defined as chords 6- and 5D.
If you like, we can dig more deeply into the mystery and try to figure out exactly what you’re playing that doesn’t sound right to your ear. Could you make a short recording of yourself playing the scale over this track so you can show me exactly which note doesn’t sound right to your ear? Our ability to resolve these mysteries through text comments alone is quite limited. But if you make an audio recording so that I can hear the sounds you’re referring to, then we’ll be able to instantly figure out what’s going on. So if that would be valuable to you, please feel free to post again with a short audio recording and I’ll be happy to listen to it.