Blender does not handle AVCHD files well. The only solution I've found to work is to convert the video files into images and add the images to Blender as image sequences. Here is the mkdir and ffmpeg commands I use to convert the video files to jpg images.
ffmpeg -i 00034.MTS 00034/image%d.jpg
Here is the command I use to play back the video during and after rendering.
mplayer -vo vdpau -vc ffh264vdpau -fps 60 -geometry 800x450 /tmp/0001_6579.avi
Here is a a video I created using this method. The video demos my Top 10 Android Live Wallpapers.