[LegionMammal978]

From the Copyright Act:

> "Phonorecords" are material objects in which sounds, other than those accompanying a motion picture or other audiovisual work, are fixed by any method now known or later developed, and from which the sounds can be perceived, reproduced, or otherwise communicated, either directly or with the aid of a machine or device. The term "phonorecords" includes the material object in which the sounds are first fixed.

So the version of the work traveling through the air is not in itself a phonorecord protected by copyright law: fair use is not even relevant for it. (However, copyright law does protect the phonorecord in the CD from being performed publicly.)

[Dylan16807]

I'm not talking about the sounds, I'm talking about the perfect digital copies in the RAM chips of the player.

And RAM is considered "fixed" by every interpretation I've ever seen.

[LegionMammal978]

Do CD players tend to keep any more than a few seconds' worth in memory? If not, you could easily argue that any given segment is too short to contain copyrightable expression. But fair use is a very particular concept about the ultimate purpose of producing a copy, which I don't think would apply to any scenario along these lines.

[Dylan16807]

Some CD players buffer a full minute or longer, and also samples have been considered copyright infringement even when they're a second long.

[LegionMammal978]

Clearly, it would be infringement if you buffered a minute of audio from CD into a player, then sold that player to someone else (without unpowering it) while keeping the CD for yourself. So I guess you might be right, and it could be fair use that allows it in the typical case (assuming it is allowed).