Sure...it's called dynamic range. Dolby Digital and DTS content can have a full range of low and high volumes. If you want everything the same level, you probably like listening to a car radio (FM is very compressed).

You didn't specify what your setup was, but I'm assuming you're just using the TV speakers. If not, you may not have your speaker setup calibrated properly. All five (or six) speakers should be set to the same level, according to Dolby specifications. Properly calibrated, dialogue should be very clear in the center speaker. If you still want to compress the dynamic levels, your DVD player and/or TV and/or receiver may have something such as a "night theater" mode.

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HR10-250, Samsung SIR-S4120R, SIR-S4080R, 2 Philips DSR704s (one connected to a Slingbox A/V). One box used the "Zipper"; rest used PTVnet to enable networking features.

Hi manotron, 

Selecting the correct audio format for your movie, when available, can also dramatically improve your sound quality when listening through TVs or other stereo devices. Read "Selecting the Right Audio Format for DVD Playback" over at TechLore.com for more information on this topc.

For some reason, when I changed my DVD-to-TV hookup from the RCA cables to S-Video, the audio level perked up considerably.