Comment 57 for bug 1386005

I've also encountered this bug on 15.04, and am currently suffering from it. I upgraded to linux-image-3.19.0-30 and this problem manifested itself, and then when -31 came out shortly after I held out hope for a fix, but thus far have had no joy. I've yet to try any of the workarounds in the bug, though, and just been booting into -28 to bypass the issue.