Extracting Front Channels from 5.1 AVCHD recordings

[Koz]

I have just recorded some music concerts with my Sony SR12. I had it set for 5.1 surround but there is a lot of background noise in the rear channels with people talking etc. I'd like to be able to just keep the front channels when I edit it, whether saving it as 2 channel or as surround and keeping the 3 front channels but muting the two rear channels. I don't want to do a full downmix and keep the rear channels as when I play it on the computer now I hear all the channels including the talking recorded behind the camcorder.

I'd appreciate any advice on whether it is possible to remix the audio with Video Studio Pro X2 as I can't see any way to do this.

Koz