libsndfile_1.0.21-3~bpo50+1.dsc refers to libsndfile_1.0.21.orig.tar.gz, but I can't find it in the queue or in the pool.
'dpkg-source -x' failed for libsndfile_1.0.21-3~bpo50+1.dsc [return code: 2].
[dpkg-source output:] dpkg-source: warning: -sn is not a valid option for Dpkg::Source::Package::V3::quilt
[dpkg-source output:] gpg: Signature made Thu Nov 18 09:47:18 2010 UTC using DSA key ID CFD42F26
[dpkg-source output:] gpg: Can't check signature: public key not found
[dpkg-source output:] dpkg-source: failure: cannot fstat file ./libsndfile_1.0.21.orig.tar.gz: No such file or directory
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