I've run across a strange behavior with a grid panel that has the MULTI mode enabled in its selection model. This only occurs when making a range selection (Shift+click). Any rows that have been selected prior to the range selection (and are outside of the new range) do not fire a deselect event when the new range selection is made. There is enough logic to remove the "x-grid-row-selected" CSS classes from the table rows that have been deselected, but the event doesn't fire. I've only been able to create this behavior with range selection. Deselecting records one at a time from a selection (Ctrl+click) works as expected.