The third installment in the pre-release series...
http://www.mars.org/home/rob/proj/mpeg/mad-plugin/in_mad-0.12.3b-pre3.zip
This version adds configurability to the automatic attenuation, and also fixes the problem with the joint stereo pie graph.
I decided it might be better to control the sensitivity of the auto attenuation rather than use a simple hard limit. The default is somewhat less aggressive than it was before (which would correspond to the "Most" setting.) The idea is to control how gradually the attenuation is increased. If only a few isolated samples clip, a less sensitive setting will attenuate less than a more sensitive setting would. Continuous clipping will continuously increase the attenuation until the signal no longer clips; the sensitivity controls how fast this occurs.
Let me know what you think.
Cheers, -rob