Animation timer seems to take too long time to expire during scrolling a qml list in Symbian device.

Using qt-components performance test application (https://qt.gitorious.org/qt-components/qt-components/trees/master/tests/manual/performancetest) it seems that FPS value is slow during scrolling. One reson for this is complicated ListItem in the delegates. I changed the delegate to be simpler one so that the list item creation takes 2-3 milliseconds and the painting time is about 8 ms. The animation timer should tick every 16 ms but it seems to be ticking every 18-20 msecs. This extra time (2-3 msecs) seems to be about the same as the item creation time. Could it be so that the timer is paused during item creation?