[ubuntu] Sound coming from both the headphones and speaker

When I plugin my headphones through the front jack in my desktop my speaker does not auto mute and sound comes from both in Ubuntu 16.04.

When I open the alsamixer program through terminal, I see that automute option is missing.

When I use SLED 12 SP1 the alsamixer program shows automute and is enabled, and also when I plug-in my headphones the speaker automutes, the same is true with Windows 7 and Windows 10.

btw my soundcard is Realtek ALC833.

My question is why the Automute option is missing?

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