I used Winavi 9 to convert mkv to avi, when i try to play the video, i can hear sounds in backround, but it has nothing to do with my video, and it sounds like the sound is played on a slow speed. Mayby is it the right audio, but it's playing very slow speed. Any ideas? I never played the original video in mkv format
You didn't check the original file? How do you know if the problem is in the converted file or the original then? If you still have the original file, check it out. Make sure it plays properly and find out what format the audio is in. Try playing it in VLC.
And what is the audio format? For example, ac-3? How many channels? Perhaps Winavi is having a problem converting the multi-channel into 2-channel stereo? Or is Winavi using the source audio as-is? In VLC you can use view/stream info to find out about the audio properties. (on both source and winavi - produced files)