I did n't have to play any more CDs , but I went back to the MP3 player later and managed to mute the cable - change noise . So at least there was a learning curve . The microphone was difficult . I expect there are better ways to hold and speak into it , as I struggled to make myself understood .
According to the above context, answer the following question.
Which of the following was not a part of the learning curve ?


No longer having to play any more CDs .