http://jsfiddle.net/shanegarner/w6sshvhg/1/
This displays the same or similar behavior to what is described. Also, it appears that the validation tool tip is tied to the “visual row index”, meaning when you scroll down the tool tip moves to the next row down. The tool tip should be tied to the actual row index so you scroll and have the tool tip stick with the right row. To see this, change the row index for the validation to 5 (see below) and then scroll down on the grid.
$(“#jqxgrid”).jqxGrid(‘showvalidationpopup’, 5, “firstname”, “Invalid Value”);