I have Lenovo Y550-4CWI laptop but as I know this issue releated to all Lenovo Yxx0 laptops. My "disable sound" hardware button have a led-indicator. This idicator work in Windows, but always not light in Linux. Photo of this button: http://img16.imageshack.us/img16/6642/76496975.jpg What hardware information I must probide?
Sorry, it's ALSA bug, not Linux kernel.