What type of camcorder is your video coming from?
Many have experienced this problem with AVCHD video.
Yes, it is SONY using AVCHD. Is there any cure to this problem?
If your camcorder shoots in 5.1 audio, ensure that your project preset is set to 5.1 audio.
Also ensure you have the latest version of Quicktime.
But other than that, no. Sorry.
OK, thank you.