Several years before the release of "The Jazz Singer" in 1927, Warner Brothers experimented with some early sound experiments using its Vitaphone division. These experiments were shown to the public where the proper sound equipment was available--and this was rarely the case but in the biggest markets. However, in the case of "Caro Nome", this experimental film was seen a bit more than most because it accompanied the release of "Don Juan"--the first full-length film with a recorded soundtrack. And, since it was such an important release, many theaters were adapted for sound and folks got to see and hear Marion Talley sing a short operatic piece from Verdi's "Rigoletto".
The clip was quite good technically for 1926. However, given the limitations of sound equipment, Miss Talley stood rather motionless in one spot for much of the song. However, towards the end, she ascended some stairs and there was a reduction in sound quality. Again, because sound equipment was so primitive, you cannot really blame the studio--and the same could be said for the jerky camera-work as she moved. Primitive, yes, but you have to start some place! Mildly interesting but extremely important to the history of film.
By the way, I think this short was originally part of a longer piece with multiple acts. That's because at the beginning you briefly catch a glimpse of a guy with a banjo AND after Talley's song, you see (briefly) a card announcing "The Kreutzer Sonata"--which you never see.