Headphones – How to Deactivate Headphones Output

I've got a broken piece of jack stuck into my headphones output : I cannot get any sound from my laptop speakers.

I've tried many things (using alsamixer, pavucontrol, checking the different mute controls and so on), but I still can't get any sound from my internal speakers.

I deactivated the automatic mute on the alsamixer, but it's still the same.

My speakers are working : on Windows (dual boot I want to stop..), I just have to deactivate the headphones output to have the speakers playing my music!

I just discovered the pactl command, which learnt me a lot about my issue. For instance, I execute the pactl list cards command, and here is a part of my output:

analog-output-speaker: Haut-parleurs (priority: 10000, latency offset: 0 usec, not available)
            Properties:
                device.icon_name = "audio-speakers"
            Part of profile(s): output:analog-stereo, output:analog-stereo+input:analog-stereo, output:analog-stereo+input:iec958-stereo, output:analog-surround-40, output:analog-surround-40+input:analog-stereo, output:analog-surround-40+input:iec958-stereo
        analog-output-headphones: Casques analogiques (priority: 9000, latency offset: 0 usec, available)
            Properties:
                device.icon_name = "audio-headphones"
            Part of profile(s): output:analog-stereo, output:analog-stereo+input:analog-stereo, output:analog-stereo+input:iec958-stereo

So ! The analog-output-speaker port is tagged as not available, and the analog-output-headphones is tagged as available.
As I said, I really can't take the broken piece of jack out of the output.

I thought that if I could completely deactivate the headphones output, my speaker output would become available, but I'm not sure.

And I absolutely have no clue about how I can achieve this.

Could someone help me, please ?

My computer is a Mac Book Pro 8.2 (device.product.name = "Apple MacBookPro8,2 [Core i7, 15\", 2011]"), and eveything else is working fine.

Thank you,

[Edit]
As asked in comments, here is a pastebin for pact list : http://pastebin.ubuntu.com/7255739/