SAVFL agents intermittent reporting to SEPM 12.1 Console

We’re having a problem with intermittent reporting by SAVFL agents (v1.0.13 and above) to SEPM 12.1.  There are 13 SAVFL agents, but we only see between 3 and 11 of them on Monitors -> Logs at any one time.  And when they do appear, the IP Address is sometimes 0.0.0.0, the virus definitions are usually up to date, and the Last Scan date is always Never.  Out Linux admin assures me the scans are running, but the info doesn’t seem to be making it to the Console.  Has anyone seen this issue before, or have any troubleshooting tips?  Are there any logs/folders/files on the SEPM host that I can check to verify the logs are being received, and what’s in them (I don’t have access to the Linux hosts)?