I just wanted to render out a composition with vegas (avi with mp3) but i don't have the option to go above 56kb 24.000 Hz (i do have lots of lower bitrates) in the render audio settings.
Do i have to install something mp3 related? i need 128kb for this video.
56 Kbps is the upper limit for MPEG Layer-3 audio encoding in AVI or WAV. This codec limitation is imposed by Microsoft, it is a built-in codec in Windows.
Please note this is _not_ the same as rendering to MP3 by selecting it from the render as dialog. The MP3 plug-in uses its own internal encoder, not the one provided by Windows. This is why you see higher bitrate options for the MP3 plug-in.