Hi, I have a macbook amateur (model 2,1) that I bought in early 2007. For a long time now it's occasionally had a micro-freeze (~1 sec, several times per day) and then I hear a small click from within the machine (maybe the hard drive?) and then everything continues as normal. Does anyone with more hardware knowledge than I know if this is normal, or should I start preparing for some sort of hardware failure? Thanks!