I have scripts that build large numbers of debian packages. When I try to set the changelog from UNRELEASED to a specific release so that I can sign the results, I get this error on every second dpkg-buildpackage:
gpg: signing failed: Broken pipe gpg: dpkg-sign.fwxloLTb/libshipscomms_4.00-1.dsc: clear-sign failed: Broken pipe
dpkg-buildpackage: error: failed to sign .dsc file
Building the same package a second time immediately after this works fine.