Here is something that bugs me and has me confused. I have installed Ubuntu on several computers all from the same CD, both for 8.10 and 9.04. On all the computers it will automatic search for libraries, plugins, etc to play media files, find them, and install them making the installation process very easy.

This is the situation on all computers except one. On this particular computer it will not automatically search for the needed files to play media files. I installed from the same CD that I installed on the other computers, so why will it not behave the same way?

To make sure, did you customize any of the other installations after the install, using Synaptic?

Stuff may have been installed differently because of sound hardware differences between the systems.

I didn't do anything differently. Like you said, it must be because of hardware differences, but it has only been on this one computer.