Discarded junk in a dump comes to life to put on a musical show.

Public domain (US): Published 1932; copyright not renewed (listed in Wikipedia 'List of animated films in the public domain in the United States', source: Hurst, Film Superlist). Source: Internet Archive (https://archive.org/details/AGreatBigBunchOfYou1932HughHarman-RudolfIsingSoundCartoon).