Update: Card Crashed while in use
 

Well an update.

The problem repeated it's ugly self again tonight with another card. right in the middle of recording a Christmas concert...boom...just stops and gives an error message for slot A. ( Didnt have any error messages before). Error message flashed was Invalid Media (A)

Starting to point away from bad and/or inexpensive media to camera issue. I'll be on the phone first thing with the JVC Field Engineer. should be an interesting conversation since this is a fairly new camera.

I'm quickly missing the days of tossing a tape in and it worked 99.9%

Further Update
 

Discovered this morning that the card that came up as invalid media was readable and I was able to pull the footage of of it. Whew!

I did talk to a JVC Field Engineer and his opinion was it was just coincidence to have two issues with cards in a week's time. He made a point about some of the card manufacturers and the ability to maintain the data rate of the camera,

I have a couple of SanDisk extremes on the way.

I've been using the 16 GB SanDisk Extreme cards with zero problems. JVC's manual recommends three types: Panasonic, Toshiba and SanDisk. They say using other cards may result in recording failure or data loss. But I know others use Transcend and other cards with no problems, so it makes you wonder.

We've been using Transcend cards in both of our 700's for almost a year now without issue. More recently, we got caught without enough media and had to resort to using CHEAP Patriot SDHC cards and they too worked with incident.