W:GPG error: http://ppa.launchpad.net precise Release: The following signatures were invalid: BADSIG AD70EA6AF76FFEBE Launchpad audiohacks, W:GPG error: http://ppa.launchpad.net precise Release: The following signatures were invalid: BADSIG FAEB83059BD4ED25 Launchpad Trimage, W:Failed to fetch http://ppa.launchpad.net/dtl131/ppa/ubuntu/dists/ubuntu/precise/source/Sources  404  Not Found
, W:Failed to fetch http://ppa.launchpad.net/dtl131/ppa/ubuntu/dists/ubuntu/main/source/Sources  404  Not Found
, W:Failed to fetch http://ppa.launchpad.net/dtl131/ppa/ubuntu/dists/ubuntu/precise/binary-i386/Packages  404  Not Found
, E:Some index files failed to download. They have been ignored, or old ones used instead.