The lesson you can learn for this is rather simple.

Do not buy test gao-gao, kaw-kaw, super-cow, cow and chicken electronic items.

Get those with personal warranty, at the very least 7 days. Because that normally is how long it takes for electronic devices to show fault.

I had a N95 once that intermittedly reboots. Took me one month to find a function that triggers the reboot (Playing the FIFA Demo). It was under warranty, and the idiot technician at Nokia Care didn't do anything but proclaimed the phone Ok. I told her to sit in front of me, and triggered the reboot in from of the whole gallery. The thing that I'm really mad was I told her the trigger for the reboot problem.

The point is this. You won't be able to test anything within a very short time.