That is correct. As discussed here #642 , the little circle ° depicts the 'nasal' information: perhaps this one? https://en.wikipedia.org/wiki/Dakuten. This "nasal" sound is pronounced by NHK presenters as standard Tokyo accent. But it's also considered outdated by some Japanese. I will add an option to hide the "nasal" sound - perhaps even the nasal sound should not be displayed by default.