Found this in Xeams.log - environment is the SYNAVM01 virtual machine (plus whatever upgrades applied automatically)

2017-12-08 16:05:01,942 ERROR l.e - Exception caught calling CLAMD on localhost/127.0.0.1: Read timed out
java.net.SocketTimeoutException: Read timed out
	at java.net.SocketInputStream.socketRead0(Native Method)
	at java.net.SocketInputStream.read(Unknown Source)
	at java.net.SocketInputStream.read(Unknown Source)
	at sun.nio.cs.StreamDecoder.readBytes(Unknown Source)
	at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
	at sun.nio.cs.StreamDecoder.read(Unknown Source)
	at java.io.InputStreamReader.read(Unknown Source)
	at java.io.BufferedReader.fill(Unknown Source)
	at java.io.BufferedReader.readLine(Unknown Source)
	at java.io.BufferedReader.readLine(Unknown Source)
	at l.e.a(ClamAVClient.java:524)
	at com.synametrics.xeams.rulesengine.custom.VirusDetector.a(VirusDetector.java:213)
	at com.synametrics.xeams.rulesengine.custom.VirusDetector.parseMessage(VirusDetector.java:52)
	at com.synametrics.xeams.rulesengine.y.a(RulesProfile.java:5849)
	at com.synametrics.xeams.rulesengine.y.c(RulesProfile.java:2928)
	at com.synametrics.xeams.rulesengine.y.a(RulesProfile.java:2275)
	at com.synametrics.xeams.connector.d.a(ProxyConnector.java:104)
	at D.e$2.run(SmtpProxyWorker.java:704)
	at java.lang.Thread.run(Unknown Source)
2017-12-08 16:05:01,944 ERROR custom.VirusDetector - Exception caught