I'm experiencing intermittent freezing with my 5 month old 9550
I've seen a similar problem for the 9560 here
The freezing mainly happens after the screen has come out of standby mode, then when using Google Chrome the mouse pointer will freeze and Chrome will momentarily say it is not responding before the machine resumes as normal, then it will freeze again and repeat over and over. The only way I found to stop it freezing was to reboot.
I also noticed that the brightness up/down buttons do not function correctly after the first freeze has occurred.
Any help or same experiences appreciated