trouble with playback of audio in movie files

[ash89]

hi, this is my first post here,
and my thanks in advance for your help.

i'll often have a movie download (say a .avi) where the audio
doesn't playback.
i have sometimes fixed this by using ffmpgx and running a conversion.
i have done this by guesswork, though,
just choosing another random audio type, say, from aac to mp3...
*this doesn't always work, so some advice on this would be appreciated.

at the moment i have one that i keep trying conversions and can't get the audio to work.
funny thing is when i go to 'play' from the ffmpgx window, the 'mplayer' plays with audio just fine.

i have attached a pic of the (current conversion attempt) ffmpgx window in this case.

can anyone help demystify this?

cheers

[Baldrick]

Buy/rent your movies instead of downloading warez releases.