Same problem in 13.04. Setting /etc/default/grub and change the cmdline to:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux"
Then update-initramfs makes Fn L/R buttons work. Brightness applet still doesn't work, but at least it remembers the Fn keys work.
uname: Linux sean-Aspire-4736Z 3.8.0-30-generic #44-Ubuntu SMP Thu Aug 22 20:52:24 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
Same problem in 13.04. Setting /etc/default/grub and change the cmdline to:
GRUB_CMDLINE_ LINUX_DEFAULT= "quiet splash acpi_osi=Linux"
Then update-initramfs makes Fn L/R buttons work. Brightness applet still doesn't work, but at least it remembers the Fn keys work.
uname: Linux sean-Aspire-4736Z 3.8.0-30-generic #44-Ubuntu SMP Thu Aug 22 20:52:24 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux