Apple appear to have archived the original discussion about background noise.
I find the noise to be prominent.
Through the (presumably low end) headphones that came with the iPod, I can't hear that much hiss, nor any whine - just as with my old 2nd Generation Shuffle.
But I still play the Shuffle in my car. I use a tape adaptor. With my 2nd Generation Shuffle, there was never any noise problem. However, the same songs - and, especially, the podcasts - played over my 4th Gen Shuffle, through the same tape adaptor, now have a loud background noise.
Many people have described this noise as a "hiss." For me, it is not simply the white noise that you might get from an old cassette recording. I am in agreement with the user who said: "Honestly this sounds more like Tinnitus than any fault on the end of the buds."
In my case, in addition to the white noise, there is a high-pitched singing from the moment you turn on the iPod - akin to the sound given off by a dog whistle, or the traditional cathode ray tube television set when it's turned on. The traditional TV whine was never that audible to many older people, people with damaged hearing, etc. But, to those with good high-end hearing, it can be noticeable - and quite annoying.
Check out this page: http://journal.plasticmind.com/ears/mosquito-tone-or-how-to-tell-youre-a-youngun /
Applying the above test, I would say that my iPod delivers a steady squeak/whistle at around 15Khz.
Additionally, when I hold the forward and backward buttons to move quickly through tracks, there is a high click akin to the sound made when you start or stop any of the test tracks from playing.
I find that the background squeak is, for some reason, less of a problem with music tracks than with podcasts.
If I turn on the Dolby noise reduction button on my car's tape-player, I can actually eliminate much of the noise. However, then the tracks are significantly muffled. I never liked using Dolby at the best of times but - since iTunes tracks were obviously not prepared in Dolby - there is a distinct fall in clarity (especially in the podcasts which contain speech) when Dolby is switched on.
The way things stand, I'm inclined to take my 4th Generation Shuffle back, and replace it with a less irritating 2nd Generation Shuffle.
Anyone else experienced this?
Do I just have a duff iPod? Should I just try replacing it with another 4th Generation model?