Starting with AVCHD from Cam WITH sound, editing and saving as m2ts then NO sound?
 

I'm shooting with a canon hf s200. It saves as avchd and when I play back the original file it has sound. When I edit in vegas platinum studio 10 and render as m2ts (sony avc) the video is perfect but there is no sound. I was advised to use a program called tsmuxer and render seperate ac3 audio in vegas and then mux the two together but even when I do that there is still no sound. I have a feeling I could get a different player or download a codec pack and it would work but what is bugging me is that it works just fine before any editing. What am I doing wrong?

BTW if I save as MP4 sound works fine.