If you have read my recent posts you'll know that I'm brand new to HD editing so I'm hoping that those of you with greater experience may be able to shed some light, or even have a remedy for some problems I'm having.
I'm using a JVC GY-HM700 to capture MP4 footage at 720 50p (I'm in UK). When I get it into Premiere CS4 I have a couple of problems. In one clip I am getting random green frames. these are full frames interspersed throughout about 1 minute of the clip and lasts for about 30 seconds, on another clip I get a few full black frames and the final problem is with the sound, partway through two long clips (about 4 minutes in) the sound suddenly goes to full bandwidth white noise for about a few minute then comes back.

I get these problems whether I play direct from the SDHC card or with the clips dragged to a hard drive (and I tried different ones). I'm sure that the clips are alright as they play back in the camera okay and I've even played them on my laptop (both from the card and harddrive).
No matter what I do I can't get them to play properly in CS4. I have deleted and recaptured them, deleted the .cfa files and everything I can think of but still exactly the same problem in the same place in the clips.

I have a work around by capturing from the camera by firewire, but that is only in standard DV quality but at least I can nick the sound.
Has anyone had or heard of a similar problem or better still have any suggestions as to what might be the cause and or a solution.

The two troublesome files are somewhere in the middle of the shoot, nos. 23 and 45 of 66 clips. They are 1.3Gb (9m 7s) and 1.8GB (12m 24s). Most are much sorter 1 - 3minutes. The wholes shoot takes up 8GB of a 32GB SDHC card. I have used the card before and since with no noticeable problem.

Any suggestions welcome.