.MOV clips are now playing as white noise in the sequences. Premiere Pro CS5

Some .Mov clips I was previously working on are all playing as white noise. Quicktime updated to 7.71 from 7.68. IS this a known issue? Should I do a system restore to take it back to the other version or are there other possibilities.

Clips are Injested SD 10 bit uncompressed....

System specs below.

Chipset: Intel x58-GigabitLAN-(6) SATA 3.0Gbps-(2) SATA 6.0Gbps-1394a-(12) USB

2.0-(2) USB 3.0-(1) eSATA
Included
CPU: Intel Core i7-960 Quad Core Processor 3.20 GHz 4.8 QPI

System RAM: 12GB (6x 2GB DDR3-1333)
System Drive: 160GB Solid State Drive (SSD) +250MBps Read/+70MBps Write

Spare Drive: 1.5TB SATA 3Gb/s NCQ 32MB Cache 7200RPM

Display Adapter: NVIDIA Quadro FX1700 512MB DVI/DVI PCI-e

Primary Optical Drive: LG Blu-ray/DVD/CD Recorder w/Cyberlink

Internal Video Raid: 2x 1.5TB SATA 3Gb/s NCQ 32MB Cache 7200RPM 3TB RAID-0

Thank you for your help!