I've already posted this on the relevant forums, but the empeg brain trust is probably more likely to be able to help. As you know, I've been ripping my DVDs to digital storage. I've been stripping out the menus, trailers, etc. Beyond that, I've not transcoded anything.

Now, when I play the DVDs back on Windows Media Center 7, I get unpleasant "auto-gain" effects. That is: if there's a loud noise (explosion, gunshot) the volume drops and then slowly ramps back up. For example, it's particularly noticable in the title sequence to Casino Royale (2006), and in The Fifth Element (1997), in the scene where Zorg is demonstrating the ZF-1.

I am using the HDMI output from an ATI Radeon HD 4350 for both video and audio. The HDMI cable is plugged into a relatively cheap (and relatively dumb) HDMI switch, and from there into the TV (a Samsung LE32R41BD). Listening is through the stereo speakers on the TV. The TV is configured with auto-gain off, and the "Standard" EQ option.

Other sources, such as recorded TV, don't exhibit this problem.

Any ideas?