Well this is an odd one. Last night I examined the "bad" ram disk with a magnifying glass and found nothing that would account for the pixilation and drop outs. The surface looked perfect. I read in a thread here that someone else had a disk with this problem, so he cleaned it and it started to work again. Well, I decided, nothing ventured, nothing gained, so I carefully washed the disk with mild detergent and a cotton ball. I dried it with a soft tissue (without aloe, and with my wife its hard to find a tissue without aloe) and put it into one of my recorders and filled it up. There were no problems this time.
How weird is that? Was something on the surface of the disk that I couldn't see but interfered with the laser? I'm at a loss, but the disk now works.