/usr/share/man/man1/mpg123-oss.1.gz is in mpg123 1.16.0-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man1/mpg123.bin.1.gz
/usr/share/man/man1/mpg123.bin.1.gz