Ffmpeg synchonization of libfdk_aac (or libfacc) and libx264

aacffmpegh.264

How to synchronize libfdk_aac and libx264 streams?

ffmpeg -i pipe_libfdk_aac.fifo -i pipe_libx264.fifo -c copy -f flv flv_stream_pipe_or_rtmp.output

I'm always receiving the same asych in all cases: saving file on file system, rtmp-using or raw pipe out.
Is it possible to syncronize them?

 ffmpeg version N-66924-gaba61b2 Copyright (c) 2000-2014 the FFmpeg developers
built on Jan 15 2015 12:50:29 with gcc 4.6 (GCC) 20120106 (prerelease)
configuration: --arch=arm --cpu=cortex-a8 --target-os=linux --enable-runtime-cpudetect --prefix=/data/data/info.guardianproject.ffmpeg/app_opt --enable-pic --disable-shared --enable-static --cross-prefix=/home/qwerty/work/android-ndk-r10b86/android-ndk-r10b/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/arm-linux-androideabi- --sysroot=/home/qwerty/work/android-ndk-r10b86/android-ndk-r10b/platforms/android-3/arch-arm --extra-cflags='-I/home/qwerty/x264 -I/home/qwerty/ffmpeg_build/mp3/build/include -I/home/qwerty/faac/output/include -I/home/qwerty/ffmpeg_sources/fdk-aac/build/include -I/usr/local/include/ -mfloat-abi=softfp -mfpu=neon' --extra-ldflags='-L/home/qwerty/x264 -L/home/qwerty/ffmpeg_build/mp3/build/lib -L/home/qwerty/ffmpeg_sources/fdk-aac/build/lib -L/home/qwerty/faac/output/lib -L/usr/local/lib/ -lrtmp -lpolarssl' --enable-version3 --enable-gpl --enable-nonfree --disable-doc --enable-yasm --enable-decoders --enable-encoders --enable-muxers --enable-demuxers --enable-parsers --enable-protocols --enable-filters --enable-avresample --enable-librtmp --enable-libfaac --enable-libfdk_aac --enable-libmp3lame --disable-indevs --enable-indev=lavfi --disable-outdevs --enable-hwaccels --enable-ffmpeg --disable-ffplay --disable-ffprobe --disable-ffserver --disable-network --enable-libx264 --enable-zlib --enable-muxer=md5
libavutil      54. 10.100 / 54. 10.100
libavcodec     56.  8.100 / 56.  8.100
libavformat    56.  9.100 / 56.  9.100
libavdevice    56.  1.100 / 56.  1.100
libavfilter     5.  1.106 /  5.  1.106
libavresample   2.  1.  0 /  2.  1.  0
libswscale      3.  1.101 /  3.  1.101
libswresample   1.  1.100 /  1.  1.100
libpostproc    53.  3.100 / 53.  3.100
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