Random files created

I have a Equalogic PS4100. It has a LUN that is passed by ISCSI to a file server. It has >14TB of medical image files on it. A large chunk of files appears to be corrupted. The file extension has changed for numerous files to a random string (xxxxxxxxxxxsuff )and all the affected files are now all the exact same size. Any ideas on what did this? Can I run a scrub on the volume to repair? I have not found any signs of ransomware and have ruled that out.