## With no audio playing - many DTS messages; rapidly

$ ffmpeg -f alsa -ac 2 -i pulse -c:a pcm_s16le -threads 0 -vn 09-14-2014-cast.wavffmpeg version git-2013-08-04-61af627 Copyright (c) 2000-2013 the FFmpeg developers
  built on Feb 19 2014 04:33:30 with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-4)
  configuration: --prefix=/mnt/video/ffmpeg/build --extra-cflags=-I/mnt/video/ffmpeg/build/include --extra-ldflags=-L/mnt/video/ffmpeg/build/lib --bindir=/mnt/video/ffmpeg/bin --extra-libs=-ldl --enable-gpl --enable-nonfree --enable-libfdk_aac --enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libfreetype --enable-libspeex --enable-libtheora --enable-x11grab
  libavutil      52. 40.100 / 52. 40.100
  libavcodec     55. 20.100 / 55. 20.100
  libavformat    55. 13.101 / 55. 13.101
  libavdevice    55.  3.100 / 55.  3.100
  libavfilter     3. 82.100 /  3. 82.100
  libswscale      2.  4.100 /  2.  4.100
  libswresample   0. 17.103 /  0. 17.103
  libpostproc    52.  3.100 / 52.  3.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, alsa, from 'pulse':
  Duration: N/A, start: 1411078878.356891, bitrate: 1536 kb/s
    Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Output #0, wav, to '09-14-2014-cast.wav':
  Metadata:
    ISFT            : Lavf55.13.101
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, stereo, s16, 1536 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
Press [q] to stop, [?] for help
[wav @ 0x2ca4f20] Non-monotonous DTS in output stream 0:0; previous: 92576, current: 92572; changing to 92576. This may result in incorrect timestamps in the output file.
[wav @ 0x2ca4f20] Non-monotonous DTS in output stream 0:0; previous: 92576, current: 92570; changing to 92576. This may result in incorrect timestamps in the output file.
[wav @ 0x2ca4f20] Non-monotonous DTS in outp
....
size=    1192kB time=00:00:06.42 bitrate=1518.3kbits/s

# ################
# With VLC playing audio - DTS messages every now and then:

$ ffmpeg -f alsa -ac 2 -i pulse -c:a pcm_s16le -threads 0 -vn 09-14-2014-cast.wav
ffmpeg version git-2013-08-04-61af627 Copyright (c) 2000-2013 the FFmpeg developers
  built on Feb 19 2014 04:33:30 with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-4)
  configuration: --prefix=/mnt/video/ffmpeg/build --extra-cflags=-I/mnt/video/ffmpeg/build/include --extra-ldflags=-L/mnt/video/ffmpeg/build/lib --bindir=/mnt/video/ffmpeg/bin --extra-libs=-ldl --enable-gpl --enable-nonfree --enable-libfdk_aac --enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libfreetype --enable-libspeex --enable-libtheora --enable-x11grab
  libavutil      52. 40.100 / 52. 40.100
  libavcodec     55. 20.100 / 55. 20.100
  libavformat    55. 13.101 / 55. 13.101
  libavdevice    55.  3.100 / 55.  3.100
  libavfilter     3. 82.100 /  3. 82.100
  libswscale      2.  4.100 /  2.  4.100
  libswresample   0. 17.103 /  0. 17.103
  libpostproc    52.  3.100 / 52.  3.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, alsa, from 'pulse':
  Duration: N/A, start: 1411079002.789931, bitrate: 1536 kb/s
    Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Output #0, wav, to '09-14-2014-cast.wav':
  Metadata:
    ISFT            : Lavf55.13.101
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, stereo, s16, 1536 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
Press [q] to stop, [?] for help
[wav @ 0x3db8f20] Non-monotonous DTS in output stream 0:0; previous: 995947, current: 995943; changing to 995947. This may result in incorrect timestamps in the output file.
[wav @ 0x3db8f20] Non-monotonous DTS in output stream 0:0; previous: 1502327, current: 1502319; changing to 1502327. This may result in incorrect timestamps in the output file.
[wav @ 0x3db8f20] Non-monotonous DTS in output stream 0:0; previous: 1617986, current: 1617973; changing to 1617986. This may result in incorrect timestamps in the output file.
size=    6313kB time=00:00:33.82 bitrate=1529.2kbits/s
video:0kB audio:6313kB subtitle:0 global headers:0kB muxing overhead 0.001237%

# ############################################

# Audio playing from a browser video - many rapid DTS messages:

$ ffmpeg -f alsa -ac 2 -i pulse -c:a pcm_s16le -threads 0 -vn 09-14-2014-cast.wav
ffmpeg version git-2013-08-04-61af627 Copyright (c) 2000-2013 the FFmpeg developers
  built on Feb 19 2014 04:33:30 with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-4)
  configuration: --prefix=/mnt/video/ffmpeg/build --extra-cflags=-I/mnt/video/ffmpeg/build/include --extra-ldflags=-L/mnt/video/ffmpeg/build/lib --bindir=/mnt/video/ffmpeg/bin --extra-libs=-ldl --enable-gpl --enable-nonfree --enable-libfdk_aac --enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libfreetype --enable-libspeex --enable-libtheora --enable-x11grab
  libavutil      52. 40.100 / 52. 40.100
  libavcodec     55. 20.100 / 55. 20.100
  libavformat    55. 13.101 / 55. 13.101
  libavdevice    55.  3.100 / 55.  3.100
  libavfilter     3. 82.100 /  3. 82.100
  libswscale      2.  4.100 /  2.  4.100
  libswresample   0. 17.103 /  0. 17.103
  libpostproc    52.  3.100 / 52.  3.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, alsa, from 'pulse':
  Duration: N/A, start: 1411079221.747001, bitrate: 1536 kb/s
    Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Output #0, wav, to '09-14-2014-cast.wav':
  Metadata:
    ISFT            : Lavf55.13.101
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, stereo, s16, 1536 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
Press [q] to stop, [?] for help
[wav @ 0x2cb1f20] Non-monotonous DTS in output stream 0:0; previous: 26836, current: 26832; changing to 26836. This may result in incorrect timestamps in the output file.
[wav @ 0x2cb1f20] Non-monotonous DTS in output stream 0:0; previous: 26836, current: 26830; changing to 26836. This may result in incorrect timestamps
...
[wav @ 0x2cb1f20] Non-monotonous DTS in output stream 0:0; previous: 26836, current: 26762; changing to 26836. This may result in incorrect timestamps in the output file.
size=      91kB time=00:00:00.63 bitrate=1168.8kbits/s
video:0kB audio:91kB subtitle:0 global headers:0kB muxing overhead 0.085981%

# ##################

# While recording screen with a browser video wunning

$ ffmpeg -f alsa -ac 2 -i pulse -f x11grab -r 30 -s 1920x1080 -i :0.0 -c:a pcm_s16le -c:v libx264 -preset ultrafast -crf 0 -threads 0 09-14-2014-cast.mkv
ffmpeg version git-2013-08-04-61af627 Copyright (c) 2000-2013 the FFmpeg developers
  built on Feb 19 2014 04:33:30 with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-4)
  configuration: --prefix=/mnt/video/ffmpeg/build --extra-cflags=-I/mnt/video/ffmpeg/build/include --extra-ldflags=-L/mnt/video/ffmpeg/build/lib --bindir=/mnt/video/ffmpeg/bin --extra-libs=-ldl --enable-gpl --enable-nonfree --enable-libfdk_aac --enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libfreetype --enable-libspeex --enable-libtheora --enable-x11grab
  libavutil      52. 40.100 / 52. 40.100
  libavcodec     55. 20.100 / 55. 20.100
  libavformat    55. 13.101 / 55. 13.101
  libavdevice    55.  3.100 / 55.  3.100
  libavfilter     3. 82.100 /  3. 82.100
  libswscale      2.  4.100 /  2.  4.100
  libswresample   0. 17.103 /  0. 17.103
  libpostproc    52.  3.100 / 52.  3.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, alsa, from 'pulse':
  Duration: N/A, start: 1411079408.154079, bitrate: 1536 kb/s
    Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
[x11grab @ 0x220d380] device: :0.0 -> display: :0.0 x: 0 y: 0 width: 1920 height: 1080
[x11grab @ 0x220d380] shared memory extension found
Input #1, x11grab, from ':0.0':
  Duration: N/A, start: 1411079408.349710, bitrate: 1990656 kb/s
    Stream #1:0: Video: rawvideo (BGR[0] / 0x524742), bgr0, 1920x1080, 1990656 kb/s, 30 tbr, 1000k tbn, 30 tbc
[swscaler @ 0x21dd0e0] deprecated pixel format used, make sure you did set range correctly
No pixel format specified, yuv444p for H.264 encoding chosen.
Use -pix_fmt yuv420p for compatibility with outdated media players.
[libx264 @ 0x22249c0] using cpu capabilities: MMX2 SSE2Fast LZCNT
[libx264 @ 0x22249c0] profile High 4:4:4 Predictive, level 4.0, 4:4:4 8-bit
[libx264 @ 0x22249c0] 264 - core 142 r2 956c8d8 - H.264/MPEG-4 AVC codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html - options: cabac=0 ref=1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=0 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=0 chroma_qp_offset=0 threads=9 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=25 scenecut=0 intra_refresh=0 rc=cqp mbtree=0 qp=0
Output #0, matroska, to '09-14-2014-cast.mkv':
  Metadata:
    encoder         : Lavf55.13.101
    Stream #0:0: Video: h264 (libx264) (H264 / 0x34363248), yuv444p, 1920x1080, q=-1--1, 1k tbn, 30 tbc
    Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, stereo, s16, 1536 kb/s
Stream mapping:
  Stream #1:0 -> #0:0 (rawvideo -> libx264)
  Stream #0:0 -> #0:1 (pcm_s16le -> pcm_s16le)
Press [q] to stop, [?] for help
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2316; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2316; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2316; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2316; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2316; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2315; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2315; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2315; changing to 2319. This may result in incorrect timestamps in the output file.
[matroska @ 0x2224460] Non-monotonous DTS in output stream 0:1; previous: 2319, current: 2315; changing to 2319. This may result in incorrect timestamps in the output file.
frame=   87 fps= 30 q=-1.0 Lsize=    1943kB time=00:00:03.12 bitrate=5096.1kbits/s
video:1360kB audio:566kB subtitle:0 global headers:0kB muxing overhead 0.869000%
[libx264 @ 0x22249c0] frame I:1     Avg QP: 0.00  size:716773
[libx264 @ 0x22249c0] frame P:86    Avg QP: 0.00  size:  7849
[libx264 @ 0x22249c0] mb I  I16..4: 100.0%  0.0%  0.0%
[libx264 @ 0x22249c0] mb P  I16..4: 28.8%  0.0%  0.0%  P16..4:  0.0%  0.0%  0.0%  0.0%  0.0%    skip:71.1%
[libx264 @ 0x22249c0] coded y,u,v intra: 2.3% 2.3% 1.9% inter: 0.0% 0.0% 0.0%
[libx264 @ 0x22249c0] i16 v,h,dc,p: 98%  2%  0%  0%
[libx264 @ 0x22249c0] kb/s:3839.43