I have recently been dealing with odd behavior from my modified ipod classic with an a256gb sd card in it, album art would be pixelated, first and second songs of an album would skip, or feeze, and just general odd behavior, and it seemed random, it would not do it all the time. so I then tried syncing my irunes library of music to another ipod classic 7th gen this one with the stock 160 gb hard drive, all has been fine until today, when in cover flow I clicked on an album to play, and the first song would just show the amount of time but would not play, skipped to second song, same thing. so now this behavior is happening on this one. I am starting to think there might be some problems with the song files, and not the ipods, they are m4a songs that I converted from flac files in dbpoweramp, I googled skipping and freezing, and there are problems like this. there are about 400 plus albums in my itunes library and it would be way to tedious to go through each one and check and try to fix errors, especially since I dont know what is exactly wrong. I thought the m4a format would be especially compatable, it is an apple format, and have read that it produces slightly better sould quality and a sucessor to mp3.