/usr/lib/x86_64-linux-gnu/libphononexperimental.so.4 is in libphononexperimental4 4:4.8.3-0ubuntu3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libphononexperimental.so.4.8.3