What is called AVL on my CRT TV?

It is Not “Audio Volume Leveler”, It Is  Automatic Volume Leveling.

Audio Volume Leveler (AVL) maintains a consistent sound level set by the viewer regardless of the channel or program. If you find yourself constantly changing the volume (ie turning it down for gunshots and then up for dialogue; turning volume up for programming and then back down for loud commercials) you should turn on the AVL. You won’t hear as much of a range in volumes when you have the AVL turned on, which may be a bad thing if you watch a lot of music videos or listen to music channels.