Question re. clip manipulation

Hello all,
 
I am having a lot of trouble with clip manipulation. It's the first time I've worked with this method. I've a 15 minute narration and I record it one paragraph at a time. During the recording I refer to sound clips that are running on a parallel track. The narration is a continuous track and I split it apart when needed, to make holes for the sound clips. It sounds simple.
 
What I find, is that the relative locations of the clips seem to magically move themselves between sessions. I also have trouble with the clips shrinking as soon as another clip is placed adjacent to it. If I try and get the clips end to end one always shrinks and has to be stretched to fill the gap.
 
I have all snaps turned off so I have no idea why they are shifting around. Any ideas?