How reliable is this? e.g., It happens every time, or x out of n sessions? When it does stop, what item type is it that it freezes on?

How arbitrary is the item--You mentioned it's after 150 items or so but what kind of variation is there here? Are we talking 149-151 sort of thing or a 140-160 kind of thing?

Also when it does freeze up after hitting a variety of keys, does it help if you click on the black border at the bottom and then pressing ctrl+alt+right (or just ctrl-right to got to the next item)?