Originally Posted by JazzGuyy
It's probably in the sources. The film stock of the early 1930s was not nearly as good as that of the late '30s onward.
Balderdash. My BD of M is from the same year as Little Caesar and it's pq is a lot better then those caps, other BDs from 1931 and before that look more promising are:
Phantome Carrrige (21)
Jazz Singer (27)
Phantom Of the Opera (25)