Comment 45 for bug 1002978

 > Lenovo B50-70 fits the description.
 > How to proceed and what info do you need, thanks!

Please file a separate bug against the alsa-driver for your issue, make sure hardware info gets attached to it (either alsa-info as per https://wiki.ubuntu.com/Audio/AlsaInfo or the standard ones that follows when you do "ubuntu-bug alsa-driver" ), then write a comment in this bug, with your machine name and a pointer to the other bug. Thanks!