micro pauses during playback

[dmp]

Hi all, been using my player for a little while now, but during playback some of the tracks have micro pauses in them, some only one or two and others constantly. All my tracks are in mp3. I have reformatted the hard drive but the problem is still there. Does anyone have any ideas how to cure this, or is it going to be a case of returning the unit as faulty.
Thanks Dave