One string (middle G) has strange over tones is this a wolfe tone or just a bad string? This harp is new to me but about 7 years old has a new set of strings and was just regulated. It is a L&H 85 E.
Does it register clearly and correctly when you test it with an electronic tuner? Also, try a harmonic on the string. Does it register clearly and correctly? If not, I’d say the string is bad.