/usr/lib/x86_64-linux-gnu/libsidplayfp.so.4 is in libsidplayfp4 1.8.3-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libsidplayfp.so.4.2.4
/usr/lib/x86_64-linux-gnu/libsidplayfp.so.4.2.4