When applying the speed effect setup for 50% then the output file has audio but a blank video using either 1-pass or 2-pass rendering.

//STARTING RENDERING: true , false , "/usr/bin/melt" , "hdv_720_25p" , "avformat" , "-" , "/tmp/kde-alpha/kdenliveC16592.mlt" , "/media/PHOTOS/Trikke-movie/test.mp4" , () , ("f=mp4", "hq=1", "acodec=aac", "ab=128k", "ar=48000", "pix_fmt=yuv420p", "vcodec=libx264", "minrate=0", "b=8000k", "g=250", "bf=3", "b_strategy=1", "subcmp=2", "cmp=2", "coder=1", "flags=+loop", "flags2=dct8x8", "qmax=51", "subq=7", "qmin=10", "qcomp=0.6", "qdiff=4", "trellis=1", "aspect=@16/9", "threads=1", "real_time=-1") , 83677 , 83821
Started render process: "/usr/bin/melt" "/tmp/kde-alpha/kdenliveC16592.mlt in=83677 out=83821 -profile hdv_720_25p -consumer avformat:/media/PHOTOS/Trikke-movie/test.mp4 progress=1 f=mp4 hq=1 acodec=aac ab=128k ar=48000 pix_fmt=yuv420p vcodec=libx264 minrate=0 b=8000k g=250 bf=3 b_strategy=1 subcmp=2 cmp=2 coder=1 flags=+loop flags2=dct8x8 qmax=51 subq=7 qmin=10 qcomp=0.6 qdiff=4 trellis=1 aspect=@16/9 threads=1 real_time=-1"
Rendering of "/media/PHOTOS/Trikke-movie/test.mp4" finished


- Kdenlive SVN 5547
- mlt-git 20110423
- ffmpeg 20110330
- x264 20110327

Alphazo

Works fine with Kdenlive 0.7.8-3 and mlt 0.7.0-3.

Not able to reproduce using x264, ffmpeg, mlt, and kdenlive from 20110420.