MacBook-Air:~ blake$ ffmpeg -f mpegts -i "udp://10.5.5.100:8554?fifo_size=10000" -c:v copy -f flv "rtmp://a.rtmp.youtube.com/live2/xxxx-xxxx-xxxx-xxxx"
ffmpeg version 4.0.1 Copyright (c) 2000-2018 the FFmpeg developers
  built with Apple LLVM version 9.1.0 (clang-902.0.39.2)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.0.1 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-gpl --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-opencl --enable-videotoolbox --disable-lzma
  libavutil      56. 14.100 / 56. 14.100
  libavcodec     58. 18.100 / 58. 18.100
  libavformat    58. 12.100 / 58. 12.100
  libavdevice    58.  3.100 / 58.  3.100
  libavfilter     7. 16.100 /  7. 16.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  1.100 /  5.  1.100
  libswresample   3.  1.100 /  3.  1.100
  libpostproc    55.  1.100 / 55.  1.100
[mpegts @ 0x7fc2c8002800] Could not find codec parameters for stream 2 (Unknown: none ([128][0][0][0] / 0x0080)): unknown codec
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, mpegts, from 'udp://10.5.5.100:8554?fifo_size=10000':
  Duration: N/A, start: 0.000000, bitrate: N/A
  Program 1
    Stream #0:0[0x1011]: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuvj420p(pc, bt709, progressive), 848x480 [SAR 1:1 DAR 53:30], 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
    Stream #0:1[0x1100]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp, 196 kb/s
    Stream #0:2[0x200]: Unknown: none ([128][0][0][0] / 0x0080)
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (aac (native) -> mp3 (libmp3lame))
Press [q] to stop, [?] for help
Output #0, flv, to 'rtmp://a.rtmp.youtube.com/live2/xxxx-xxxx-xxxx-xxxx':
  Metadata:
    encoder         : Lavf58.12.100
    Stream #0:0: Video: h264 (Main) ([7][0][0][0] / 0x0007), yuvj420p(pc, bt709, progressive), 848x480 [SAR 1:1 DAR 53:30], q=2-31, 29.97 fps, 29.97 tbr, 1k tbn, 90k tbc
    Stream #0:1: Audio: mp3 (libmp3lame) ([2][0][0][0] / 0x0002), 48000 Hz, stereo, fltp
    Metadata:
      encoder         : Lavc58.18.100 libmp3lame