I'm having this issue as well. I just tried the following mainline kernel per the instructions above and the symptoms are the same.
Linux gilmour 3.12.0-999-generic #201311020446 SMP Sat Nov 2 08:48:35 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
(I had this problem mid 13.04 as well, but didn't spend any time looking into the cause at that time...)
I'm having this issue as well. I just tried the following mainline kernel per the instructions above and the symptoms are the same.
Linux gilmour 3.12.0-999-generic #201311020446 SMP Sat Nov 2 08:48:35 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
(I had this problem mid 13.04 as well, but didn't spend any time looking into the cause at that time...)