Key press capture hiccup

[Snowball]

This may have already been asked and it is probably OS oriented, but I am trying to make linear movement of an object with key presses. The only problem is that the way the keys are captured by QT, has a hiccup after the first key press, which is quite noticeable. I was wondering if there was a way to prevent this hiccup, either via QT or the OS.

I'm using QT Library 4.7.4 with QT Creator 2.4.1 on Windows 7.

Please note that this code will be transferred to my linux (Xubuntu 12.04 LTS) workstation once I have the QT SDK download for linux.