Reproducible: Always
The mpd 0.16.4 ebuild tried to process the patch mpd-0.16.4-ffmpeg.patch, due to the following line in the ebuild. epatch "${FILESDIR}"/${PN}-0.16.conf.patch \ "${FILESDIR}"/${P}-ffmpeg.patch From looking at the source, it looks like this patch has already been applied upstream. So it should be removed from the ebuild.
+ 04 Sep 2011; Michael Weber <xmw@gentoo.org> mpd-0.16.4.ebuild: + ffmpeg patch now in upstream, remove unneeded and failing eepatch line (bug + 381725 by Josh) +