ReadyNAS 4312 is unstable. I can't get access to shares or logs

We have a ReadyNAS 4312; running firmware 6.10.8 

I can no longer access the shares over the SMB network. I can see the device on the network, but when I try to see the shares under it, it either 1) times out or 2) asks me for a credentials due to “Access is denied”. No matter what credentials I enter (NAS Admin or Active Directory), it still won’t allow access to shares.  I never get a list of available shares.  The User Accounts are synced to our Active Directory.

I sometimes can’t see the shares via the Shares\Shares menu. If I reboot the NAS, I can usually see them for a while before they disappear (Shares\Shares menu). I can always see the shares and drill down into them via Shares\Browse (but it's slow).

I sometimes can’t see the File Backups I have configured. If I reboot the NAS, I can usually see them for a while before they disappear.

Navigating some menus causing the spinning circle to come up for a long time before it is ready (populates).

System\Performance shows utilization is fine – not over utilized.

If I try to download the logs, it hangs. I have logs from 12/07/23 before this issue started. They are attached. The issue started on 12/12/23. I haven't been able to get logs since then.

In the middle of navigating thru the admin settings, I intermittently get the message "Connecting to the ReadyNAS Admin Page". That is usually followed by the message "ReadyNAS Admin Page is offline". Sometime later I'll get the login prompt and can log back into the unit. I have a continual ping to the unit and it never loses ping when this happens so it does not appear to restart.

It seems like if I reboot the NAS, what about 30 minutes to come online and settle down, I can access the menus.  If I make any configuration changes, that's when it slows to a crawl.  But even after restart, I can't access the Shares nor can I download logs.  I haven't had access to Shares for 4 days.