Without knowing the details of the issue, I suspect it may be related to Azure datacenter load balancer and TCP keep-alives. Checkout out this jira ticket as it explains the issue and how to solve it: https://issues.couchbase.com/browse/DOC-554
Here is a link that shows how to enable logging: http://docs.couchbase.com/developer/dotnet-2.1/setting-up-logging.html
Note that in a production environment, using a verbose log setting like DEBUG will degrade performance, but show the most detail.
-Jeff