更新时，我收到以下错误消息：
W: The repository 'http://ppa.launchpad.net/mc3man/trusty-media/ubuntu xenial Release' does not have a Release file.
在这里，我找到了关于此错误的另一个声明：如何在使用 PPA 或更新我的软件包列表时修复 404 错误？
这建议删除某些 PPA；而且，我不确定我是否应该这样做，因为这可能意味着无法获得我需要的更新。
这是我应该做的吗？
执行apt-get-update 后，我总是收到以下错误消息：
Reading package lists... Done
W: The repository 'http://ppa.launchpad.net/ubuntu-audio-dev/ppa/ubuntu xenial Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Skipping acquire of configured file 'main/binary-i386/Packages' as repository 'http://dl.google.com/linux/chrome/deb stable InRelease' doesn't support architecture 'i386'
E: Failed to fetch http://ppa.launchpad.net/ubuntu-audio-dev/ppa/ubuntu/dists/xenial/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have …