kevin@videobox:~$ ffmpeg -i Videos/Leahy-1.mp4 -f mpv plughw:NVidia,3
ffmpeg version N-74595-g6be5b05 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (Debian 4.9.2-10)
  configuration: --prefix=/home/kevin/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/home/kevin/ffmpeg_build/include --extra-ldflags=-L/home/kevin/ffmpeg_build/lib --bindir=/home/kevin/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree --enable-libv4l2
  libavutil      54. 31.100 / 54. 31.100
  libavcodec     56. 58.100 / 56. 58.100
  libavformat    56. 40.101 / 56. 40.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 37.100 /  5. 37.100
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.101 /  1.  2.101
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Videos/Leahy-1.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp42mp41
    creation_time   : 2016-02-14 15:15:31
  Duration: 00:06:12.93, start: 0.000000, bitrate: 10355 kb/s
    Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 1280x720, 10032 kb/s, 59.94 fps, 59.94 tbr, 60k tbn, 119.88 tbc (default)
    Metadata:
      creation_time   : 2016-02-14 15:15:32
      handler_name    : Alias Data Handler
      encoder         : AVC Coding
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 317 kb/s (default)
    Metadata:
      creation_time   : 2016-02-14 15:15:32
      handler_name    : Alias Data Handler
[NULL @ 0xabef580] Requested output format 'mpv' is not a suitable output format
plughw:NVidia,3: Invalid argument