Hello. I finally got it to work with ALL of my USB pen drives. I used a mac (Snow Leopard) so I'm not sure how this would work with Windows.
1. Insert your USB drive into your Mac
2. Open up Disk Utility
3. Highlight the USB drive the left column
4. Click PARTITION (not ERASE).
5. On the Volume Scheme, choice 1 partition
6. Click the OPTIONS Button and chose MASTER BOOT RECORD
7. Click OK
8. Name the drive what your like
9. Choose FAT as your FORMAT
10. Click APPLY
And voila! Every disk of mine now works flawlessly with the EDGE. One might try this on a malfunctioning SDHC card, though I haven't yet as mine worked out of the box.