ReadyNAS Ultra drops connection

About 2 weeks ago my ReadyNAS Ultra 2 started dropping it's connection to all the computers in my house every few hours or so. It also becomes unresponsive. While I can see the CIFS and AFS shares being advertised clicking on either of them either times out or takes minutes to respond. Rebooting the NAS gets everything back to normal for another few hours. Even Frontview becomes very slow. This started on RAIDiator 4.2.24. I tried reinstalling 4.2.24 and also upgrading to 4.2.25 (which I'm now on) but neither resolved the problem.

Things I've tried already:
-Reinstalling RAIDiator 4.2.24
-Upgrading to RAIDiator 4.2.25
-Issue is the same from my OS X machine (recently upgraded to Mavericks) and from my Windows 8 computer
-SSH'ing into the box and running top doesn't show anything abnormal and when the issue happens my SSH connection is terminated (broken pipe)
-I tried restarting the AFP and CIFS services while the issue was happening but it didn't solve the problem
-I've shut down all other services on the NAS except for AFP and CIFS but the issue still occurs
-I managed to download logs from Frontview while the issue was occurring. It took several minutes for the logs to download instead of a few seconds. Any pointers on which log may show the most relevant information for this type of issue?

Any pointers on diagnostics I can run to find out what's happening or on what could be causing this? The NAS is a few years old and nothing in my setup has changed over that time except for the recent upgrade on one of my computers to Mavericks.

Thanks.