Comedian Harmonists - Wenn der Wind weht [take 2]

HMV master OD 490-2, rec. Berlin, 14 August 1931.
Ari Leschnikoff (1st Tenor), Erich Collin (2nd tenor), Harry Frommermann (3rd tenor), Roman Cycowksi (baritone), Robert Biberti (bass), Walter Joseph (piano).
This is a very rare alternate take (a few copies of this master were pressed accidentially at the German plant) of one of the few recordings the Harmonists made in the months when Erwin Bootz had temporarily left the group. The group reheased for a while with Bootz' Friend Fried Walter at the piano, but finally agreed on Walter Joseph as their new pianist (Fried Walter later played with the Humoresk Melodios and decades later wrote a beautiful arrangement of "Veronika, der Lenz ist da" for the King's Singers). Walter Joseph had several decades of experience with light music, playing for and together with Rudolph Nelson in the latter's various cabaret productions.
Both sides were unhappy, though: Bootz' carreer did not take off in the way he expected, and the record company was not happy with Walter Joseph, for his comparatively big tone proved to be difficult to record. So Bootz finally returned to the Comedian Harmonists after only a few months of absence.
It is not a hundred percent clear when Joseph recorded with the group, but there are four surviving recordings of this particular song (two in German, one in French and one in English), and on all four the piano part is absolutely identical. So I presume it is rather unlikely that this is Bootz playing, who never wrote down his piano parts, but rather played semi-improvising following the singers' score.
The photo of the Harmonists reheasing in the recording studio is one of only a handful of snapshots that show Joseph playing with the group.