Hi, I am trying to take an existing .mkv file and change it to a MOV container, while transcoding the audio to AAC. I need a MOV container with MPEG4 or MPEG4/AVC (H.264) and AAC in order to play back the video on my xbox 360. Anyway, the input file in this case is one of the sample Matroska files on www.matroska.org. It is MPEG4 video and Vorbis audio, but I've tried this for other Matroska files (H.264 video, AC3 audio) and the same error occurs. First of all, here is the command line I'm using: ffmpeg -i starwars10MB-1.mkv -vcodec copy -acodec libfaac -ab 128k sw.mov With this command, I get the warning: WARNING codec timebase is very high. If duration is too long, file may not be playable by quicktime. Specify a shorter timebase or choose different container. Then later on during the transcoding process, I get an error: FATAL error, file duration too long for timebase, this file will not be/s playable with quicktime. Choose a different timebase or a different container format I tried using an mp4 container instead, and it gives me the warning above but not the error. However, the resulting mp4 file is unplayable in Quicktime and in VLC the video is garbled/unviewable. If the input source is H.264 video, the resulting mp4 file has a bogus bitrate and a reported fps of 1000! Here's the version info for ffmpeg: % ffmpeg -version FFmpeg version SVN-r10258, Copyright (c) 2000-2007 Fabrice Bellard, et al. configuration: --prefix=/home/floyd/local --make=gmake --disable-debug --enable-memalign-hack --enable-shared --enable-pp --extra-cflags=-I/usr/local/include/vorbis -msse -I/usr/local/include --extra-ldflags=-L/usr/local/lib -la52 --extra-libs=-pthread --enable-gpl --enable-pthreads --enable-liba52 --enable-liba52bin --enable-libfaac --enable-libfaad --enable-libfaadbin --enable-libgsm --enable-libmp3lame --enable-libogg --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid libavutil version: 49.5.0 libavcodec version: 51.42.0 libavformat version: 51.12.2 built on Aug 28 2007 22:55:34, gcc: 3.4.6 [FreeBSD] 20060305 ffmpeg SVN-r10258 libavutil 3212544 libavcodec 3353088 libavformat 3345410 Is this a bug in the Matroska decoder/demuxer? Or am I doing something wrong? Has anyone else had success converting mkv to mov, maintaining the video stream as-is (for MPEG4 or H.264)? This is a crucial step for me to be able to view things on the 360. :) Thanks in advance! Josh