Hello, I installed AVS video editor and made a few videos without problems. But now I'm making a video and the time mark is constantly changing. I'll try to explain it. I plan to put a certain piece of footage at 1:12 because that goes well with that particular place in the song. But after I filled the line with pieces of film or trim them, that place suddenly has the mark 1:17. The line for audio mix where I put the MP3 is locked so it can't be shifting. Is anyone here familiar with this problem?