I have observed this problem constantly when using the default kernel in wheezy linux-image-3.2.0-4-amd64 3.2.39-2
Today I tried a 3.8 kernel and I noticed that this problem with notifications has gone away linux-image-3.8-trunk-amd64 3.8.5-1~experimental.1 -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
