Kubuntuを使っています。　Muon Update Manager　1.3.1の「Check for Updates」で下記のエラーとなります。

Failed to download http://extras.ubuntu.com/ubuntu/dists/precise/Release.gpg Could not connect to extras.ubuntu.com:80 (91.189.92.152). - connect (110: Connection timed out) Failed to download http://extras.ubuntu.com/ubuntu/dists/precise/main/source/Sources Unable to connect to extras.ubuntu.com:http: Failed to download http://extras.ubuntu.com/ubuntu/dists/precise/main/binary-i386/Packages Unable to connect to extras.ubuntu.com:http: Failed to download http://extras.ubuntu.com/ubuntu/dists/precise/main/i18n/Translation-ja_JP Unable to connect to extras.ubuntu.com:http: Failed to download http://extras.ubuntu.com/ubuntu/dists/precise/main/i18n/Translation-ja Unable to connect to extras.ubuntu.com:http: Failed to download http://extras.ubuntu.com/ubuntu/dists/precise/main/i18n/Translation-en Unable to connect to extras.ubuntu.com:http:

一時的に相手が止まっているだけでしょうか。