"Play that funky music" is a song by the band Wild Cherry. The song has its origins in the fact that WC were finding that venues for rock and roll were becoming few and far between as venues converted to take account of the new disco craze. The band were still continuing to play rock and roll in these discos but the crowd would often ask them to play funk or disco. The band resisted this for a long time, not feeling that they could or should but eventually the drummer said, 'Perhaps we really should play that funky music, white boy,' meaning that despite the fact that they were a white band, they should have a go at playing funk, which they did and scored a major hit in the process.
So, er... where's the racism? Merely mentioning race does not make something racist. It is not racist to say Nelson Mandela is black. It is not racist to say the Queen is right. It is not racist to say funk music is mainly played by black musicians, or that heavy metal is mainly played by white musicians. It's racist to say that only black musicians can play funk, but it was precisely the opposite; it was black crowds asking a white band to play funk - i.e. it wasn't the band's race they had a problem with, it was their style of music.