What are synch-rights?

The concept film production rights is also known as (a work’s) synchronization rights, that is, a right to associate works from different genres, here: a form of projection, such as films + musical works in the form of recordings, or rather, sound recordings. In this way, a new work is created. For this purpose, the film producer must concede the available rights, so the music can be used in the film. The film production rights are granted by the authors themselves or by a publisher, as long as the authors commissioned their exploitation.

Proud Music Library for royalty free music and production music
Synch-rights means: “film plus music”