When you as an editor are sending a quicktime (no .wmv's, please) to a mix session, the order of elements in the file you send should be as follows: (Times noted are relative.)
1. ~Three seconds of black (from 55:00-58:00). Two seconds would be fine as well. One second is not enough.
2. One frame of the video of your choice, together with one frame of 1kHz sine wave audio. (at 58:00 only) (It never hurts if the number "2" appears somewhere in this frame to reinforce that this frame is "T-minus 2 seconds" from the first frame of program.)
3. Two seconds minus one frame of black. (from 58:01-1:00:00)
4. Your program (first frame of program should fall at 1:00:00)
5. One second of black (minimum) after last frame of program.