[MacRuby-devel] NSTableView contents goes blank

Hi all, I've got a NSTableView that works fine except for a small detail. If the application runs in the background (window is open, but there are other windows open in front of it) for a long period of time, the contents of the tableview goes all white (blank). Clicking within the tableview or scrolling within it redraws the the contents of the table, but I would rather this not happen. I am scrolling the tableview periodically, one row at a time, so this may be the issue. After I scroll it, I do call reloadData on the table though, and this still happens. I've noticed this on two systems. Has anyone seen this issue? Thanks, Daniel