Dell :: Hddmovies Or Music Stops Playing For A Very Short Time Simply Said Playing Isn't Smooth

I bought new Dell E4300 with 7200 rpm harddisk. Notebook is nice except one problem I have - every 2 seconds or more (this differes a lot on resources usage) movies or music stops playing for a very short time ... simply said playing isn't smooth.

I think it could be a HDD problem so I run HDTune benchmark.

Here is the result ... while I didn't make 15 posts I can't post a link (!@#$@$@#) anyway I think the result shouldn't look like this:

[url]

Almost in every low point of the graph the video or music stopped playing for a very short time (300-600ms) and that is very annoying.

I think it could be a hdd problem or maybe CPU problem that affects the hdd results as well, because the mouse pointer also stops moving for a while.