[FFmpeg-user] FFMPEG dshow option and libx264 video grab devices issue

[gustas noiws]

I am having a problem with dshow/libx264 encoding in FFMPEG and publishing across librtmp.
My command line run very well for couple minutes (hours, sometimes) and drop frames a lot  after. 
I use many types of the video capture devices and diresctshow driver (webcam fake) getting same effects for all.
My version is FFmpeg git-fd0b8d5 32-bit Shared (2012-02-11) , but the issue ocurr in 64-bit version too.
My command line is: 

ffmpeg -loglevel debug -f dshow -framerate 15 -channels 1 -i video="webcam or directshow driver here":audio="webcam or directshow driver here" -pix_fmt yuv420p -sample_fmt s16 -vcodec libx264 -s 352x288 -vb 300k -r 262144k/16384k -g 120 -vprofile baseline -preset ultrafast -tune zerolatency -level 21 -acodec libvo_aacenc -ab 32k -ac 1 -ar 22050 -async 1 -threads 0 -f flv "rtmp://localhost:1935/ffmpeg/teste"

Last debug info:

RTMP_SendPacket: fd=1164, size=175
  0000:  44 00 00 14 00 00 af 08                            D.......
  0000:  af 01 01 46 37 94 d0 64  30 bd 04 26 00 a0 c0 42   ...F7..d0..&...B
  0010:  c1 52 46 84 d9 d8 5a d4  b0 d4 6a 74 01 af fa f6   .RF...Z...jt....
  0020:  11 86 9b c3 15 ac ae fc  68 c4 0e 56 51 43 4e dd   ........h..VQCN.
  0030:  66 4d d5 75 5c 99 21 33  df be 32 56 9a d6 56 b6   fM.u\.!3..2V..V.
  0040:  f9 f9 bc 3e 15 d2 e7 4b  c6 07 0b b1 ce bc 26 50   ...>...K......&P
  0050:  64 05 22 50 6c d2 aa c1  e0 6c 82 7d 72 07 25 21   d."Pl....l.}r.%!
  0060:  76 a6 84 2b 08 1e e5 7b  4e f0 4b a3 13 12 2b c4   v..+...{N.K...+.
  0070:  e7 28 ee 95 bd 95 81 7f  6d c9 fc be d1 97 c3 3d   .(......m......=
  0000:  c4                                                 .
  0000:  b7 71 8d e8 d0 c5 9e b6  62 dc a4 8f 25 66 eb d7   .q......b...%f..
  0010:  af 23 d7 96 49 85 c2 6c  5b 4c c3 7b 99 46 a8 52   .#..I..l[L.{.F.R
  0020:  12 ac 22 bb f1 ba f0 45  89 83 0b 08 62 96 7c      .."....E....b.|
[libx264 @ 010E9200] frame=56333 QP=25.00 NAL=2 Slice:P Poc:106 I:1    P:199  SK
IP:196  size=1798 bytes
frame=56334 fps= 15 q=25.0 size=  146336kB time=01:02:43.63 bitrate= 318.5kbits/
frame=56334 QP=23.00 NAL=2 Slice:P Poc:108 I:1    P:275  SKIP:120  size=3043 byt
es
[libx264 @ 010E9200] frame=56335 QP=23.00 NAL=2 Slice:P Poc:110 I:1    P:233  SK
IP:162  size=1825 bytes
[dshow @ 0003B3E0] real-time buffer 66% full! frame dropped!
[dshow @ 0003B3E0] real-time buffer 100% full! frame dropped! *** (has RTMP stream dropped) ***
    Last message repeated 32466 times



Any advice welcome.