Guys, im sorry but replacing it is not the right way to go.
I had the same problem with my Droid, and i figured some app i installed should be the reason of the problem.
What i did was, i went on settings, then accounts & sync and i unchecked facebook app (which was the one i suspicious about).
Then i restarted the phone and BINGO!
I had another problem on my droid and all i had to do was going on setting and then privacy and then "factory data reset". And that solved the other problem i had.
So if the first doesnt work for you try the second!
By the way, my case was FB app, but maybe, just maybe if you have other apps, might be any!
Hope i could help.