I am writing about this only because it has happened twice in a row, and may help to determine if in fact there are anomalies with the BookPort using four gig cards. Twice now, I helped a friend upload Audible books to their four gig card on the BookPort, and after each time, the unit's keys wouldn't do anything. All we heard occasionally was "BookPort 2.3.3.0 ready," or something very similar. Taking out the batteries and resetting the unit did not change a thing, which makes me suspect that the card had an anomaly each time possibly created by the unit which it couldn't handle. Since I didn't have a card reader, I plugged in the bookport to the computer using the USB cable, and did a "check for errors" on the disk with the fix files automatically and recover bad sectors boxes checked. After almost 45 minutes, it finally got through Phase one, then gave me the message that scandisk or chkdsk (I forget which was running) couldn't finish the operation and closed before conducting phase two. The unit was still inoperable with none of the keys doing anything I could tell. I finally hit the four corner keys to reformat the card, and believe it or not, hitting that combination seemed to unstick whatever was keeping the unit locked up, and all worked well after that. I had to hit that combo a few times, but at some point, I can't say exactly when, the unit began functioning as it should, and all files were there and working, including the three Audible files I had uploaded. Very strange, and it may make no sense, but I am hoping that it may give a clue to Pam, Rob, or Larry about a possible source of a problem with the BookPort writing to four gig cards. Don