My board suddenly does not boot correctly or crashes.

The boot stops displaying ROMBOOT or halts in U-Boot.
The kernel crashes randomly.

If your board runs a bootstrap prior version 3.4 (bootstrap 3.4 prints version information, older versions do not), the problem should be solved by updating.

The new images can be found here:
http://www.armbedded.eu/node/629

Update procedure:
1) launch SAM-BA and choose board according to:
http://www.armbedded.eu/node/8
2) run NANDFLASH "Enable NAND flash" script
3) run from SAM-BA console: NANDFLASH::EraseBlocks 0 0x1ffff
4) run "Send Bootfile" script with the appropriate image for your board

For even newer Stamps also consider the following download:
http://www.armbedded.eu/node/675