Right, I was just checking you are not on ADSL. Changing the notification timeout will reduce the number of warnings, but not help you solve the actual problem. The missed samples usually have a reason.
Please have a look in the logs of your application server. You might find Java-monitor related stack traces in there.
I usually look up the threads graph (since it is nice and solid) and see if there are tiny vertical lines through it that show missed samples. Things I have seen in the past were late GC pauses of 60 seconds or more and network issues, like broken network adapters, bad cables or routing issues.
Broken network adapters usually result in large number of errors on the adapter. Your OS will report these somewhere. Since you mention remote desktop I assume you are on Windows, and I know nothing about Windows.
It is there somewhere, I am sure.
On other machines I ran a traceroute every 5 mins for a week to a known working machine to see if there were intermittent router issues. There were in my case.