Mouse wheel doesn't scroll Upper window display correctly

[tgioiosa]

My mouse wheel does not scroll the BTP uppermost window contents smoothly. It doesn't matter whether displaying recipes, indgredients, etc., the list will not scroll unless I spin the wheel hard & fast and then it moves around 3 lines at a time. It won't scroll slowly one line at a time.

I'm using a standard Microsoft optical wheel mouse, and it works fine in all other applications (Windows 7 64-bit OS). In all these other apps, a slight movement on the wheel will scroll smoothly one line up or down.

Anyone else seen this behavior?