Help, please.....We are two long-distance (domestic US) Mac users with Powerbooks and Leopard who are finding our iChats constantly interrupted by video freezes. The audio continues to work, but the images pixelate and then freeze. Any suggestions? And, if it's common, is there a fix or software update? And, if it can't be fixed, any alternatives to iChat? Thanks -- please send replies to "firstname.lastname@example.org"