Seeker said:Deinstalled bin oss ...
As I like to have all locally compiled, instead downloading bin packages I used portdowngrade, to get oss-4.2.b2005
After compilation soundon && mpg123 -z ...
Voila! It works!
Now, _1 indicates change on maintainers side (the way he implemented port), and THAT is source of error.
If I was going to official oss's forum, I would be wasting my time.
Please try the attached patch. Just replace the old patch with this file in /usr/ports/audio/oss/files.