Hello,

My ASUS A6B00U notebook (in A6U series) is also affected by frequent 
head unloads, mentioned here:
http://ata.wiki.kernel.org/index.php/Known_issues#Drives_which_perform_frequent_head_unloads_under_Linux

I've applied the fix by adding to /etc/rc.local a line:
hdparm -B 254 /dev/sda
so if these affect attached logs, I can change it for a while and send 
them once more.

-- 
Regards,
Michał Gołębiowski