Hey guys! I have my MBP Alu since October 2008 and so far I am just in love with the machine. The only problem that started to appear recently is the black thin lines that appear on the screen for a very short period of time (shorter than 1 sec) and disappear very quickly. Imagine just a very thin black horizontal line appearing in some place on the screen. See the picture, please: http://i43.tinypic.com/2q0vwy9.png It doesn't happen that often... maybe 2 times in an hour. When it happens, I use the integrated Nvidia 9400M graphic chip. I see it a lot when I use Firefox and listen to the music through AirTunes. Maybe there is a connection between those two things. Sometimes I see it just on the desktop without Firefox turned on. To be honest I start to worry about my laptop. Maybe my graphic card is about to die. I have been hoping that the recent update 10.5.7 would solve the issue, but it is not the case.. Can anybody help me? Should I call Apple? I cannot miss my laptop as I need it now for my study..