Sox + MP3: libsox-fmt-mp3 not working

Question

My server threw this error

Sox::Error (sox FAIL formats: no handler for file extension `mp3'
)

This person (https://superuser.com/questions/421153/how-to-add-a-mp3-handler-to-sox) had a similar issue. The solution listed there was

sudo apt-get install libsox-fmt-mp3

After running this I still was getting the same error, so I uninstalled sox (sudo apt-get remove sox) and then reinstalled it. At this point I'm confident they're both installed with the newest versions since any attempt to install them yields this

libsox-fmt-mp3 is already the newest version.
sox is already the newest version.

However, I still am receiving the same error.

Any idea what I'm missing?

Edit:

I'm using the ruby-sox gem (https://github.com/TMXCredit/ruby-sox) which says the below should be sufficient.

apt-get install libsox-fmt-all sox libchromaprint-dev

But all those are installed and still no dice.

Edit:

The only way I can figure this to happen is if sox is looking for the lib files in the wrong place. With that in mind these details might be helpful,

sudo find / -name sox
/usr/bin/sox
/usr/lib/x86_64-linux-gnu/sox
/usr/lib/mime/packages/sox
/usr/share/doc/sox
/home/deployer/apps/eko/shared/bundle/ruby/2.1.0/gems/ruby-sox-0.0.1/lib/sox

sudo find / -name libsox-fmt-mp3
/usr/share/doc/libsox-fmt-mp3

When I uninstall sox (apt-get remove sox) then I get this when I search for sox

ubuntu@ip-10-0-0-9:~$ sudo find / -name sox
/usr/lib/x86_64-linux-gnu/sox
/home/deployer/apps/eko/shared/bundle/ruby/2.1.0/gems/ruby-sox-0.0.1/lib/sox

To get rid of this sox and hopefully return to a no sox anywhere except the gem experience, I tried

sudo apt-get remove libsox-dev 

which told me a)libsox-dev wasn't installed and b) I needed to

sudo apt-get autoremove

to remove a host of files related to sox that were no longer needed. At this point, besides the gem, there were no sox files. I then

apt-get install libsox-fmt-all sox libchromaprint-dev

As the gem suggested.

No dice. Same error.

Answer 1

Ult decided to just use wavs. Months later (aka now) requirements changed and in order to support IE I had to get mp3 support up and running. All of the above issues still applied.

Ended up using lame.

system "lame -b 32 --resample 8 -a #{Rails.root.join("tmp",@filename)} #{Rails.root.join("tmp",@output_file_name)}"

Answer 2

I ran into this issue as well. For me the problem is that I was receiving an audio stream that I thought was mp3 but which was actually aac. Sox doesn't have a handler for aac, but switching to ffmpeg worked like a charm:

ffmpeg -i input.aac output.wav