I just discovered something strange while editing a waveform. I selected the beginning section of the waveform then used the zoom tool from the timeline and dragged down from the center of the selection to zoom in. While the highlighted section got larger, the waveform scrolled off the page to the right. when I hit play I could still hear the audio but the section that was now highlighted was a silent section before the audio started. Then, when I use the zoom tool to drag left or right, the highlighted section moves proportionately with the mouse but the waveform does not (it moves slower).
 
Has anyone experienced this?
 
Update: So, I bounced the clip to a new one and the problem is gone. Never mind.