I am getting a weird flash frame error using mkvmerge. All I did was uncheck commentary tracks and non-English subtitles, crop the black bars and remux to mkv. The following error occurs every time and is not present in Harmy's original:

Edit - remuxed the m2ts file exactly as is and this error still occurs. It skips back to an earlier frame and chops off the top of Ben's head moving it to the left. I have done this a half a dozen times and it always reproduces the same error. Any ideas?

FIXED: It appears that it was mkvmerge GUI that caused this error. I downloaded the 2.1 AVCHD again and remuxed to the same result. Then I updated mkvmerge GUI, remuxed again and this time got no error.