Just bumping this thread up to get it noticed again. I too am having the same problem and have been ever since I upgraded to 6.12 from 6.03. I am using WinXP if that makes a difference. I ran the varies write testing scripts that people posted and get the same numbers (or very close depending on other writes that occur too).

It Stoped Working After 32767 Tries.  

Here are links to three other threads reporting this same bug. PLEASE fix this!

report 1 report 2 report 3