First, update your libraries to the latest versions outside of the Ubuntu services. If you run the compilations from multiple windows (as I often do), then remember to run ldconfig after you are done so that ffmpeg can load all of the newly compiled modules.
Keep the same quality level: ffmpeg -ss 00:00:00 -t 64 -i test.mp4 -vcodec copy -acodec copy -sameq test_clip.mp4