There are many different DIN connectors.
The RCA connector is inherently flawed in that there is no standard i.e. there is no guarantee that a given male will mate snugly with a given female, always a bad thing. There are other connectors that are much better, such as DIN and XLR, but we seem to be stuck with the RCA for single ended equipment. Some manufacturers such as Naim tried to get away from them but it never really caught on. Now Naim equipment comes with DIN and RCA connections.
The RCA connector is inherently flawed in that there is no standard i.e. there is no guarantee that a given male will mate snugly with a given female, always a bad thing. There are other connectors that are much better, such as DIN and XLR, but we seem to be stuck with the RCA for single ended equipment. Some manufacturers such as Naim tried to get away from them but it never really caught on. Now Naim equipment comes with DIN and RCA connections.