On previous occasions, some faced this issue due to free space on application server. Also if you have a load balancer or an external proxy, then there is a chance that the client that initiates the request is closing before receiving a response. This is probably due to a timeout configuration set up in the proxy which you will have to increase so that it will wait longer for the response before closing.
However, it was found in situations where a customer who met none of the above requirements still had the issue. They had enough space on application server and also did not use any load balances/proxy.
However after recommending a clean build the issue was resolved. Maybe that can help future issues.