system/IO-TCP/selectors msg was not delivered ! akka 2.5.19

Message [$Unregistered$] from Actor[akka://sms/system/IO-TCP/selectors/$a/4#-1951800158] to Actor[akka://sms/system/IO-TCP/selectors/$a/4#-1951800158] was not delivered. [1] dead letters encountered. If this is not an expected behavior, then [Actor[akka://sms/system/IO-TCP/selectors/$a/4#-1951800158]] may have terminated unexpectedly, This logging can be turned off or adjusted with configuration settings ‘akka.log-dead-letters’ and ‘akka.log-dead-letters-during-shutdown’.

akka 2.5.19

Just started seeing this as well. Did you figure out the issue?

More details about during what circumstances you see these would be good, is it using the TCP streams, remoting, Akka IO directly, client/server etc?