If it turns out to be an overly tight primary chain due to the auto adjuster, trying to adjust the auto adjuster will likely be a waste of time. This doesn't seem to be a major issue on late model bikes like it was in the first few years of the auto adjusters, but nothing made by man is perfect and you could have gotten a bad one. You could replace it with another auto adjuster and hope you get one of the good ones, or you could go with various aftermarket adjusters. Those aren't necessarily guaranteed solutions either, as various adjusters like the Screamin' Eagle manual adjuster or the Baker manual adjuster have been reported by users to be noisier than the auto adjusters.
Don't just assume this is a primary chain and adjuster noise. Once you have the primary cover off you can verify if the primary chain tension is too tight. If it isn't, you need to look at other items like the IPB I mentioned previously.
Jerry