RN4220 / Ver6.9.2 - File Access Not Possible / "clamd" CPU usage on the NAS 99.9%

Dear Netgear Community, we are an experiencing a problem with one of our customer's NAS and I was hoping you could help us. The Model and Firmware version are as follows: RN4220 / Ver6.9.2. The problem our customer is having is that it becomes impossible to access folders and files on the NAS. About ten users use the NAS in the office, and periodically between 7 and 8 users lose the ability to access files on the NAS even after successfully logging in. After which only restarting the NAS  resolves the issue. Sometimes it is necessary to restart the NAS several times to resolve the issue, and sometimes the users even need to restart their PCs as well. When we investigated the issue from our offices (remotely), we found that it seems to be caused by an abnormally high CPU usage on the NAS itself. When we checked the NAS CPU usage with the "Top Command", CPU usage on the NAS shows as much as 99.9%. It appears the "clamd" process is in a runaway state. As this is an anti-virus daemon in Linux, we tried to use the "kill" command to stop it, but, it recovers eventually and the problem rearises. We are wondering if the process is attempting to connect to a server to update the virus definition files, etc., but is failing. If that is the case, can you let us know where it’s trying to connect so we can trouble shoot and allow it if necessary? Or if you have seen this before and there is any known solution to this could you let us know? If you need any other information or logs etc., please let me know. I am looking forward to hearing from you. Best Regards, Christopher Modica.  (the password for the attached log is: nttc2netgear)