What I don't understand is why omxplayer doesn't have this problem, or is it also using ffmpeg-compat?
There has been an api change between ffmpeg 1.0.x and ffmpeg > 1.1.x (an explanation was given here: [Prototyp] RPI Ausgabeplugin) - the plugin author himself uses ffmpeg 1.0.8. I had originally posted my problem including some sound samples here: [Prototyp] RPI Ausgabeplugin
Building with the original Makefile on Arch Linux ARM would build and link everything against ffmpeg 2.2 which causes the sound problems. Using my Patch the plugin is built and linked against ffmpeg 1.0.10:
$ ldd /usr/lib/vdr/plugins/libvdr-rpihddevice.so.2.1.6 | grep ffmpeg-compat
libavcodec.so.53 => /usr/lib/ffmpeg-compat/libavcodec.so.53 (0xb63a1000)
libavformat.so.53 => /usr/lib/ffmpeg-compat/libavformat.so.53 (0xb6291000)
libavutil.so.51 => /usr/lib/ffmpeg-compat/libavutil.so.51 (0xb5fba000)
And I don't really know what ffmpeg-compat does
This package provides ffmpeg 1.0.10
After applying this patch I get a "Segmentation fault (core dumped)"
Did you set the environment-variable for pkg-config before calling make?