Refactor: decrease code complexity of M4A Class

Split long functions into more shorter ones
Refactor: decrease code complexity of MP3 Class
Refactor: decrease code complexity of MP3 Class
Refactor: decrease code complexity of MP3 and M4A
Refactor: decrease code complexity of M4A Class
Refactor: decrease code complexity of M4A Class
Refactor: decrease code complexity of MP3 Class
Refactor: decrease code complexity of MP3 and M4A
Refactor: decrease code complexity of MP3 and M4A
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