audio in the video sequencer

Some questions about the sequencer.

1.What is the difference between loading audio HD and audio RAM. What benefit is there to loading audio into ram or from the harddrive?

  1. I am trying to use the sequencer to edit NTSC footage. I’ve used a speed control to sync the video up with the audio, but whenever I try to kut it the speed control sends the video all out of whack. I tried forming a metastrip with the effect but blender doesn’t let you kut metastrips at all!

Thanks!