Adorno's theory of music starts with the divide between popular and serious music. Popular music is what is seen as recognised at the time in our culture. His theory leads us to believe that standardized 'pop' music are essentially the same. His theory talks about how we are listening to the same sound over and over and that 'pop' music has to keep within certain rules and limitations. Pseudo-individualization is what Adorno refers too for this standardization. This is where people are lead to believe that they are all being different, with different tastes etc, however in reality we are all buying the same stuff, interested in the same things etc.
Adorno stresses about how a song being 'plugged' (played continuously) it will get recognition and become popular with listeners.
Below: Leona Lewis' cover of 'Run' by Snow Patrol sets a prefect example of how a cover which had previously been a massive success can be altered or sang by a different artist and once again have massive media coverage and recognition.