Spontaneous Failure of Linksys Router

I had an interesting service call today involving a Linksys BEFW11S4 Version 4.0. I installed this router a little over 3 weeks ago and everything seemed to be working fine. After I returned from my recent trip, the owners informed me that it had stopped working.

I finally got to “lay hands” on the unit today and it was immediately clear that its firmware was corrupted or missing. The unit flashes its power light to indicate this condition. Luckily, even with damaged firmware, you can still re-load the correct firmware.

After downloading the latest firmware from Linksys and a bit of fiddling with network settings, I was able to connect to the router and re-install the firmware. The unit immediately woke up and started to function. Upon logging into the unit, I realized that the new firmware was version 1.5. If I remember correctly, the unit came with 1.47.x originally. The look and feel of the new firmware is quite different.

My question to you is this…what would cause a spontaneous failure of the firmware in this router? The users did nothing to the unit, they wouldn’t know how. They say that there had not been a power failure or any power problems. While I am glad I was able to restore the unit, I would like to try and discover what caused it to fail in the first place.