Originally Posted by Michael of Lucan
This is normal. Wikipedia insists on using a format that can't be read by a large proportion of users. Large numbers of users have no control over the contents of the PCs which they use at work or indeed at home. An encyclopedia should be available to everyone, not just people with well-brought up equipment.
Wikipedia uses the Ogg Vorbis format, which is a completely free and open audio codec and container format. If the encyclopedia should be available to everyone, as you say, it should also be available to those who are not willing or able to pay for patent licensing fees for proprietary audio formats such as MP3.