'You hear that? That whistling sound? Whooooooooo!' one astronaut says. Another answers, 'It sounds like, you know, outer space-type music.' 'Well, that sure is weird music,' the first guy concludes.
The 'music' lasted the whole hour the capsule was on the far side of the moon.
Magnetic field or atmosphere interference? Nope. The moon has no magnetic field and not enough atmosphere to interfere with radios.
The origin of the 'music' remains a mystery.