Playing edited video, 1080/60i mp4

I am trying to use WD TV Live to play video files from my edit program Final Cut Express.  These are encoded into Quicktime MP4 format at 1080/60i (same as what the camera uses).  I want to feed the TV a 1080/60i signal via HDMI, so I set the WD TV Live to 1080/60i output.  Half the time when I start a video, I get an excellent result–smooth motion, no artifacts  Other times a  problem occurs when there is horizontal movement in the video.  I get double images at the moving edges.  This happens on all the TVs I tried.  Here is what it looks like:

Bad Image 1

Bad Image 2

Bad Image 3

Here is what it looks like when the image is “good”:

good image

This only happens with 1080i files and the WD TV set to 1080i.

Anyone have any idea what is wrong?

EDIT:  This result also happens on component output.

That looks like the encoder is combining 2 interlaced frames.  Are you sure you’re encoding back to 1080i/60 and not 1080p/30?

I know you said the WDTV is set to 1080i/60, but it looks like you’re only making a 30fps .m4p file.

Thank you for your response.

I generated the files using FCE export and made sure to not select “deinterlace source video”.  I have also generated files from MPEG StreamClip, also specifying interlaced output.  I have no reason to think that these are other than 1080/60i.  I have also made progressive files using both programs, they come out 1080/30p.  These actually play cleanly on the WD TV Live using either 1080i or 1080p settings on the WD unit.  The 1080p output just duplicates frames to get from 30p to 60p.  The result is that motion is not smooth and the Sony  “Smooth Motion” frame interpolation doesn’t work well.

I repeat, half the time I get a good, clean playback from the 1080i files, and when that works, it is perfect.  However, every time I start or pause and restart the video, i risk going into the “bad” mode.

I should also mention that the TV reports the input as 1080i/60, so the WD unit is outputting what it is set to.