OK, so this quote does not exactly mention an iPod, but let us consider the morals of our Founding Fathers in our nation, our Puritan heritage in relation to our obsession with all things music:
“If you would have your sons soft, womanish, unclean, smoothmouth, affected to bawdry, scurrility, filthy rimes, and unseemly talking; briefly if you would have him, as it were, transnatured into a woman or worse, and inclined to all kinds of whoredom and abomination, set him to dancing school and to learn music, and then you shall not fail of your purpose.
“And if you would have your daughter riggish, bawdry and unclean, and a filthy speaker, and suchlike, bring her up in music and dancing and my life for yours, you have won the goal.”
–Philip Stubbes, 1583
anti-itch meditation 
This man was dead-on. And that was written regarding the music and dancing in those days, which would be considered harmless in our time. What would he have said about the music and dancing in our time? I think he would have been stunned speechless.
The iPod, for the most part, is a tool of slavery. It allows people to put themselves into a dream-world environment, so that they become slaves to music-induced good feelings. Once people are addicted to good feelings, they can be very easily manipulated by their own passions, or by the bribes and threats of others.
I’ve been reading the Holy War (by Bunyan) to my son recently, and was struck by his description of the soul of man as a city with different gates, represented by our senses: eye-gate, ear-gate, etc. If these gates are not guarded, the soul will be easily taken.
Prov. 4:23 – “Keep thy heart with all diligence; for out of it are the issues of life.”