Не могу добавить репо после обновления до 12.04 LTS

Я полный новичок в Linux. Я только что обновил с 10.04 до 12.04 LTS, и все виды вещей начали работать неправильно. Одна из основных проблем заключается в том, что я не могу добавлять репозитории.

Пример:

sudo add-apt-repository ppa: team-xbmc

выводит:

Traceback (most recent call last):   File "/usr/bin/add-apt-repository", line 8, in <module>
    from softwareproperties.SoftwareProperties import SoftwareProperties   File "/usr/lib/python2.7/dist-packages/softwareproperties/SoftwareProperties.py", line 53, in <module>
    from ppa import AddPPASigningKeyThread, expand_ppa_line   File "/usr/lib/python2.7/dist-packages/softwareproperties/ppa.py", line 27, in <module>
    import pycurl ImportError: librtmp.so.0: cannot open shared object file: No such file or directory

/etc/apt/sources.list

# deb cdrom:[Ubuntu 10.04.1 LTS _Lucid Lynx_ - Release i386 (20100816.1)]/ lucid main restricted
# deb cdrom:[Ubuntu 10.04.1 LTS _Lucid Lynx_ - Release i386 (20100816.1)]/ maverick main restricted
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.

deb http://archive.ubuntu.com/ubuntu precise main restricted
deb-src http://archive.ubuntu.com/ubuntu precise main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://archive.ubuntu.com/ubuntu precise-updates main restricted
deb-src http://archive.ubuntu.com/ubuntu precise-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://archive.ubuntu.com/ubuntu precise universe
deb-src http://archive.ubuntu.com/ubuntu precise universe
deb http://archive.ubuntu.com/ubuntu precise-updates universe
deb-src http://archive.ubuntu.com/ubuntu precise-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
## team, and may not be under a free licence. Please satisfy yourself as to 
## your rights to use the software. Also, please note that software in 
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://archive.ubuntu.com/ubuntu precise multiverse
deb-src http://archive.ubuntu.com/ubuntu precise multiverse
deb http://archive.ubuntu.com/ubuntu precise-updates multiverse
deb-src http://archive.ubuntu.com/ubuntu precise-updates multiverse

## Uncomment the following two lines to add software from the 'backports'
## repository.
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
# deb-src http://pt.archive.ubuntu.com/ubuntu/ lucid-backports main restricted universe multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu lucid partner
# deb-src http://archive.canonical.com/ubuntu lucid partner

deb http://archive.ubuntu.com/ubuntu precise-security main restricted
deb-src http://archive.ubuntu.com/ubuntu precise-security main restricted
deb http://archive.ubuntu.com/ubuntu precise-security universe
deb-src http://archive.ubuntu.com/ubuntu precise-security universe
deb http://archive.ubuntu.com/ubuntu precise-security multiverse
deb-src http://archive.ubuntu.com/ubuntu precise-security multiverse
# deb http://ppa.launchpad.net/stebbins/handbrake-snapshots/ubuntu precise main # disabled on upgrade to precise

Понятия не имею, что делать дальше. Должен ли я просто отказаться от этой установки и начать с нуля, или это поправимо? librtmp.so.0 также отображается в журналах ошибок, которые я начал получать из XBMC (я не уверен, что это важная информация).

Заранее благодарю за любую помощь, которую вы можете мне оказать!