iPhone 4 doesn't keep music play count?

Hello!

Recently I noticed that when I connect my iPhone to my computer at work to listen to my music on the PC (this is not the computer I sync with), the play count shows up incorrectly.

For example, I could've listened to a new album I bought a couple of times already, and when it shows up on the computer the play count will be 0.

Is my iPhone not keeping a correct play count? Is there a way to correct this?

Any help is appreciated.