kernel - Ubuntu 15.10: laptop reboots after suspend

When I open the lid after suspending my laptop, the laptop reboots instead of waking up normally. However, this only happens when it's on battery.

This only happened today after Ubuntu performed some minor updates, I believe.

I am using Zenbook UX305 with ubuntu 15.10 and I am using kernel 4.5.0 rc6.

A while ago, I had this problem but I was using the original Ubuntu 15.10's kernel which is version 4.2. But installing kernel 4.5.0 fixed the problem until recently - which is weird.

Now I am facing the same problem. The fact that the kernel didn't change, I am lost as to what is causing it.

Cheers.