Read Bill Hunt on a file type as WRAPPERhttp://forums.adobe.com/thread/440037?tstart=0
What is a CODEC... a Primer http://forums.adobe.com/thread/546811?tstart=0
What CODEC is INSIDE that file? http://forums.adobe.com/thread/440037?tstart=0
Report back with the codec details of your file, use the programs below
For PC http://www.headbands.com/gspot/ or http://mediainfo.sourceforge.net/en
For Mac http://mediainfo.massanti.com/
Once you know exactly what it is you are editing, report back with that information... and your project setting, and if there is a red line above the video in the timeline, which indicates a mismatch between video and project
Welcome to the forum.
One possible cause of truncated Audio, and especailly where the Waveform Display goes flat-line, is that Conforming was interrupted. See this ARTICLE for more info on conforming. One must let it complete 100%. I do not touch the computer, while this process is on-going. With less powerful computers, trying to edit too soon, has caused equipment crashes.
If that is NOT the cause, then please tell us more about your MOV files, your camera, your Project Preset, and how you are getting the MOV files into PrPro. This ARTICLE will give you some background on what is important, and this ARTICLE will give you some background on the MOV (AVI, WMV, etc. too) wrapper.