Comment 46 for bug 1229591

I made a clean installation of 14.04 yesterday but unfortunately the problem with the brightness keys is still present.

Have there been any developments as regards isolating the culprit?

It is very strange considering that the keys worked just fine up to 13.04 and kernel 3.8.

I don't know if it helps but the key combination (Fn+F4 and Fn+F5) is like it is dead. I do not get any feedback/result from acpi_listen when pressing them.

In case you have any news, please let me know.
Thank you.