I use this arguments: -oac lavc -ovc lavc -of mpeg -mpegopts format=dvd:tsaf -vf scale=720:576,harddup -srate 48000 -af volume=0 -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9800:vbitrate=5000: keyint=15:vstrict=0:acodec=ac3:abitrate=192:aspect=16/9 -ofps 25 -o salida But the volume is not 0. Why?