Xilisoft Video to Audio Converter is a video to audio converter. It can extract audio from MPEG, MOV, WMV, AVI, DVD, VCD, SVCD, 3GP, AVI and save to popular audio formats such as MP3, WAV, AAC, AC3, WMA, m4a, MP2, OGG, au. It can also rip between different audio formats. All codecs are build-in, so you can keep the default setup, select certain audio codec, and set the parameters of output. It also supports batch conversion and multithreading.
There is a limitation of 5 minutes on this shareware version. This product worked very good. I used it to translate a wave to an mp3 for a web page. It can do sample rate as low as 32. The interface is not very clear, but works well. The cost is $25.00 to get rid of the nag!