Ubuntu 10.04 has 2 important bugs since 13th of June - with all updates installed -.

The first problem is with the sound. What you should do is to avoid putting the sound on mute, because you won't be able to start it again. This is what I did yesterday. And now I realized that I don't have sound anymore. It doesn't matter what settings I give to the system in sound preferences, because on the bar it just displays the speaker followed by three lines (3x "-"). This means that the sound is muted, even if in all my settings the sound is on. Of course that "waking up" the sound would be theoretically possible with third-party programs from the Software Center, but I'll let my system like it is, just to see how much it takes for developers to fix this.

The other problems is related to the...shutdown. Here it is a critical bug, which brings you to the login screen, when you select shutdown. I don't know why, but now the shutdown button has the same functionality as the log out one. Practically, there is now way to shut down your system from the OS. In case that you are here, what you can do in order to shutdown your system is to push and keep the power button on your PC/Laptop for 5 seconds (this cuts the power of your computer), or to unplug it from the power source (if you are on a laptop, use the first option). Both are improper ways of shutting down the system, but there is no alternative.

Note: My Ubuntu is up-to-date, at 9:15 GMT time, Monday, 14th of May, and the problems are not fixed. If an update appears in the update manager which fixes these problems, I'll update this article.