Some times but not all when the freeze occurs, there are the two message multiple times in the SQL Agent Log:

[382] Logon to server 'MANNASQL2' failed (ConnAttemptCachableOp)

[165] ODBC Error: 0, Unable to complete login process due to delay in opening server connection [SQLSTATE 08001]

I have seen little resource on this except perhaps the Domain Controller pass through is suspect.

No other messages are seen in any event logs or server logs.