Please see https://roundup.mplayerhq.hu/roundup/ffmpeg/issue348 for the full
report.

My platform is Ubuntu Linux 7.10 i386, running on a Pentium Core Duo 1.83 GHz
notebook PC with 2GB RAM.

These two videos were recorded using the latest SVN from 2008-2-12.

The video x11grab-overmuxed-no_audio.avi was recorded using only x11grab, with
no audio capture. Notice that it has a very aesthetically pleasing framerate.

The video x11grab-overmuxed-audio.avi was recorded to capture both from
x11grab and from /dev/dsp. Notice how jittery the framerate is. Also notice
the bitrate does not increase nearly as quickly as the no_audio recording.

I used a fixed video bitrate in this, but similar results are obtained using
-qscale.