An RF error in PDP led us to believe that the R&S RF generator was no longer communicating with the DAQ machine. We made an access, bringing a spare R&S to check out the situation. After rebooting the R&S, the error went away. Apparently the memory was corrupted temporarily, probably by radiation. We left the spare R&S in the labyrinth in case it is needed in the future. We are going to pursue a remote reboot solution to prevent the need for an access should this problem recur.