All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
This kind of sale is not permissible because it is a form of gambling and deceit, which are forbidden, because the CD's are different, and the fact that the buyer is satisfied with all of them is of no consideration because satisfaction does not render forbidden contracts permissible.
Abu Hurayrah said, “The Prophet forbade the sale of pebbles and the sale which involves Gharar (deceit).” [Muslim] [The sale of pebbles is by throwing a pebble on a number of goods and buying what the pebble lands on]
“With regard to the prohibition of the Gharar sale; it is a great principle of the Book of Sale Transactions. This is why (Imam) Muslim gave it precedence. It involves countless matters such as the sale of a slave who fled from his master, the sale of something that is nonexistent, selling an unknown item, selling something that one is unable to provide (for the seller), selling something that the seller does not own, the sale of fish in the sea, the sale of milk in the udder (i.e. before it is milked), selling foodstuff that is not specified, the sale of a dress among many garments, and a sheep in a herd [without defining which one], and similar kinds of sale. All these sales are invalid because they involve deceit without a need.”
Allah knows best.