To be more descriptive here's a live example: http://interklub.biz/CTPonLine.html
In last column there's a ComboBox with some values. When user choose an option in ComboBox from first row and then scroll down the first choice disapears (comes back to default state). There's something more strange, earlier I've tried to apply a one more ComboBox in additional column, with highly dynamic values (completly different for different rows), but with after same action (scroll down and then scroll down) values dataProviders from different ComboBox were switch.