I just purchased 2GB RS-MMC off ebay for my 770.

The card works fine in the 770, but I can't use my USB card reader with it. I've tried it four or five times, and the last few times, the card is unreadable, and I get a message that it's unformated. Interestingly, the first time I used the card in the card reader, I was able to transfer the entire 650MB of a video before getting an error message at the end.

The card reader is about 2 or 3 years old. I have been using it for a 2GB MMC card with no problem--this is the thing that gets me! Both the MMC card and the RS-MMC card are from TOPRAM, and are supposed to be 100x speed.

Has anyone else have similar problem? I think/hope the problem is the card reader. Can anyone recommend where I can get a compatible card reader, or anything I should look for, in trying to get a working USB 2.0 card reader. It took almost two hours to transfer 650MB using USB 1.1 connection to the 770.

I have the same issue with my 2gb kingston.
With the usb cable, works fine.
Plugged into the SD slot on the Dell laptop, lots of errors.

desiv

As a follow up:

I got another SD/SDHC/MMC/RS-MMC card reader. The reader is able to read other cards, but my 2GB RS-MMC was unreadable and rendered corrupted when I used the reader.

Fortunately, I just purchased a N800 recently, and am able to use it to read/write the 2GB RS-MMC, using high speed through USB cable. I guess I will have to use this as a workaround, until I can stumble upon a card reader that works with the card.