From Klaus Wunderlich’s online biography:
Klaus released his first recording in 1958. There followed more than 120 LPs, Cassettes and CDs over 40 years, with sales of more than 20 million copies worldwide. Klaus received 13 gold discs and 1 gold cassette.
Who, in the history of recorded music, ever heard of anyone anywhere ever receiving a ‘gold cassette’? Is there any tragically 70s band that appeals to long-distance drivers who sold the requisite amount to be awarded a gold 8-track cartridge?
Just quietly, I reckon Klaus spraypainted his gold cassette himself!