PM866 Fault

Hi .... I have a tech support case opened up for this and waiting for a call back, but wanted to post a message here as well... we had a PM866A (non redundant) go into fault mode; F LED is red, P LED is green. When I look at the controller log, what I see is:

This PM has been unintentionally stopped.
Reason:
- Soft Error Upset detected by the FPGA

Press init button or remove power to restart...

What could cause this error? Should I be thinking about a redundant processor; would that help for a case like this?

thanks