On 25.02.2012, at 19:16, Carlo Bongiovanni wrote: > C:\Shell\ffmpeg\bin>ffmpeg.exe -i D:\XXX.mov -s 320x240 -r 30000/1001 > -b:a 200k -bt 240k -vcodec libx264 -acodec libmp3lame -ac 2 -ar 48000 > -ab 128k ../output.mp4 Looks like -b:a and -ab are used at the same time. Remove -ab. HTH!