I have a new video camera and when I import video using pre organizer it saves them as a AVCHD and when I play the video back on Media Player they are clear but when I play them in pre they are pixilated and grainy. My new camera is a JVC HD with a 60gig hard drive. I also have another a helmet camera which is also HD and stores the video on a SD card. When I download the video from that camera the are clear and they are saved in MPEG-4.
Have you ensured that your Premiere Elements project is set up for AVCHD video and, if necessary, 5.1 audio?
When you add video to your timeline, is there a red line above the clips? If so, press Enter to render the timeline (The red line will turn green). Does this improve performance?
As for your helmet cam, that video is MP4 but is not AVCHD and so will not work in Premiere Elements without a conversion, per the FAQs to the right of this forum.