To reproduce:
KDENLIVE build 0.7.9 rev. 5427
Project defined as either DVD Wide screen NTSC or HD 1080p 29.97 fps
add 1 clip (either MTS or MKV) source file format is 1080p 30 fps, 45 seconds long
Drag it to video 1
Pressing Play in Clip Monitor and Project Monitor both play the expected audio
Press the Render button
Destination DVD
Format NTSC
Scanning Auto
Either Export Audio or Export Audio Automatic
Encoder threads either 1 or 2 (CPU is Intel Core i5)
Render to File
Play the rendered VOB file in VLC,Xine, Kaffeine. Picture looks great, Audio is mute.
Re-render the same project as YouTube 1280x720 and the Audio is present.

That is good news.
Any tips on what I can/should change/check? Maybe install ffmpeg from source as well?
OpenSuse 11.3
KDE 4.5.5
Kdenlive and MLT installed from source
ffmpeg installed from Packman Repository version 0.6.26387svn-1.pm.3.5
ffmpeg -version
FFmpeg version SVN-r26387, Copyright (c) 2000-2011 the FFmpeg developers
built on Feb 9 2011 23:26:26 with gcc 4.5.0 20100604 [gcc-4_5-branch revision 160292]
configuration: --shlibdir=/usr/lib64 --prefix=/usr --mandir=/usr/share/man --libdir=/usr/lib64 --enable-shared --enable-libmp3lame --enable-libvorbis --enable-libtheora --enable-libspeex --enable-libopenjpeg --enable-libxvid --enable-postproc --enable-gpl --enable-x11grab --extra-cflags='-fmessage-length=0 -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables -fasynchronous-unwind-tables -fPIC -I/usr/include/gsm -I/usr/include/openjpeg' --enable-debug --disable-stripping --enable-libschroedinger --enable-libdirac --enable-libgsm --enable-avfilter --enable-libvpx --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-libdc1394 --enable-pthreads
libavutil 50.36. 0 / 50.36. 0
libavcore 0.16. 1 / 0.16. 1
libavcodec 52.108. 0 / 52.108. 0
libavformat 52.93. 0 / 52.93. 0
libavdevice 52. 2. 3 / 52. 2. 3
libavfilter 1.74. 0 / 1.74. 0
libswscale 0.12. 0 / 0.12. 0
libpostproc 51. 2. 0 / 51. 2. 0
FFmpeg SVN-r26387
libavutil 50.36. 0 / 50.36. 0
libavcore 0.16. 1 / 0.16. 1
libavcodec 52.108. 0 / 52.108. 0
libavformat 52.93. 0 / 52.93. 0
libavdevice 52. 2. 3 / 52. 2. 3
libavfilter 1.74. 0 / 1.74. 0
libswscale 0.12. 0 / 0.12. 0
libpostproc 51. 2. 0 / 51. 2. 0
Thanks