This is needed desperatly for regular TV. On some channels ad volume is much higher then mov volume so when ads start during chillex movie you get totally stressed.
My Toshiba TV has that feature built-in - they call it "TruVolume". It detects sudden increases in the program's volume, and adjusts accordingly. You can turn the feature on or off. I think it may also turn the volume up when the program's volume goes down.
