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Hello everyone - I am really sorry if this is not in the correct place (I think it isn't), but I honestly didn't quite know where to start this thread.

So my problem concerns mp3s. I will start from the beginning, so this will be quite a long post (please bear with me, as my big adventure did not begin on Windows).

I was listening to some music on Amarok (Ubuntu), when suddenly, halfway through the song, the playback became faster, garbled and generally corrupted-sounding. I tried switching to some other songs by that artist, but they were all garbled in the same way. The playback of all of the mp3s in one other artist folder were affected too.
However, all my other mp3s played without any problems so I ignored this small glitch. I am not sure if it makes a difference, but of the two folders, one contained my own rips and the other mp3s I had purchased online.

After this I sent my PC back home, during which time it got rather bashed around (long story), ruining the hard disk on which my music was stored. I was, however, able to rescue some of it, and it is now on an external HDD.
I wasn't able to test these files on the PC due to lack of speakers, so I copied them onto my mobile to find that ALL of them now sounded garbled.
I then used the external drive to test them on iTunes on a Macbook. Still garbled.
On the Macbook, I discovered that some mp3s actually sounded normal - basically all of the ones that I had ripped recently. All of the ones that I had ripped a long time ago, or had bought online, were garbled.

THEN (bear with me), I came to Japan, where I am currently using a not-extremely-new laptop running Windows XP Home. Except for the ones in the two folders (now deleted) which suddenly got garbled in Ubuntu, all of my mp3s play without any problems in WMP.

However, all of these mp3s still sound garbled when I play them from the same laptop using iTunes, as well as when I attempt to play them on my iPod.

This all led me to think it is some sort of codec problem, but I am not really sure where to start, as I don't know much about how mp3s work but it seems like it's them and not the software used to play them that is the problem. I mean iTunes/a Macbook/an iPod should be more than equipped to play mp3s, right?

Is there anything I can do from Windows to get the mp3s to sound normal on other devices or platforms, as I don't have access to a Macbook yet?

Thank you for reading! I hope someone can help me. I can provide one of the mp3s for analysis if it would help (I ripped them from a CD I bought and it can be deleted afterwards, so I hope that it's alright).