What is the point of the volume & headphone jack on many drives?

[Technarch]

The dvdrom 163D that I killed in an accident, had a play and next button… testing it out, it would only do all the work itself if I hit the buttons myself, otherwise everything would go through the OS.

So on a cd/dvdrom drive that has a volume and headphone jack, what is the point if there is no play button?

Is this why some manufacturers are removing those two things from the bezels?

[rdgrimes]

the headphone jack is a monitor of the analog audio output. The volume is there, well, to control the volume. It’s simply a convenience, particularly if you don’t have an audio card, for those who want to play audio on the computer. Most systems auto-play audio CD’s.