RCA mono recording?

This MGM short has opening credits that list RCA as the sound recording system. On the Warner Archives DVD, the sound is of poor quality. Much of the dialogue is not understandable.

Played on modern TV sets, the mono recording may be a mess. But RKO used the RCA sound recording system. DVDs of RKO's movies from the 1930s have sound that is still clear as a bell. Most other studios used Western Electric sound.

Any other explanation why Trocadero music and dialogue seem so bad?

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