linux 3.6.x and 3.7rc1 have some problem with bbswitch module, So far eighter downgrade to 3.5.x or disable (if you even have that option in bios) Optimus. Maybe just remove bbswitch module but this way your system may overhead.
Oh. It seems to do with the system bell caused by konsole. After changing previous blacklist file /etc/modprobe.d/blacklist to /etc/modprobe.d/blacklist.conf . with "blacklist pcspkr", it seems to be fine now.
I tried this instruction https://github.com/Bumblebee-Project/bbswitch.And I tried to blacklist nvidia_uvm and nvidia modules.However it is still automatically turned on. It's annoying to manually turn it off...What should I do?