Oh How Happy is a song written by Edwin Starr.
[1] In the early 1980s, it was a minor hit for New Zealand based New York City soul singer Herb McQuay.
While the band was at Golden World recording background vocals and some demos, Edwin Starr - who happened to be there and liked their sound - approached them with an unfinished song of his.
According to member Nick Marinelli, the band actually had an active role in the final product, but they were not credited.
Starr cited Shades of Blue's youth and inexperience for not knowing how the assigning of credit worked.