Once, a guy called Simon Wai travelled to Hong Kong.
This was some years after the Sonic 2 was released.
There he was going to see how good Sonic the Hedgehog 2 was being there.
So, he purchased the game there, and when he started to play, he realized something strange.
In the "sound test menu", there had a song that wasn't in the American version! This song didn't belong to any stage and.. it was a sad song.
and he returned to America, he told to others people who discovered that others countries also received this "special" cartridge. Even I myself had lol
This song nobody could explain why is there and why is a sad song.