java/net/MulticastSocket/Test.java fails intermittently

Only observed once with JDK 11 b10
Output as below:
----------System.out:(53/1499)----------
**********************
Test 1: /224.80.80.80
Join: /224.80.80.80
Send packet to: /224.80.80.80
Got packet! - Good.
Send packet to: /224.80.80.80
Got packet! - Good.
Leave: /224.80.80.80
No packet received within timeout! - Good.
Join: /224.80.80.80
Send packet to: /224.80.80.80
Got packet! - Good.
Send packet to: /224.80.80.80
Got packet! - Good.
Leave: /224.80.80.80
No packet received within timeout! - Good.
Test passed.
**********************
Test 2: /ff01:0:0:0:0:0:0:a
Join: /ff01:0:0:0:0:0:0:a
Send packet to: /ff01:0:0:0:0:0:0:a
Got packet! - Good.
Send packet to: /ff01:0:0:0:0:0:0:a
Got packet! - Good.
Leave: /ff01:0:0:0:0:0:0:a
No packet received within timeout! - Good.
Join: /ff01:0:0:0:0:0:0:a
Send packet to: /ff01:0:0:0:0:0:0:a
Got packet! - Good.
Send packet to: /ff01:0:0:0:0:0:0:a
Got packet! - Good.
Leave: /ff01:0:0:0:0:0:0:a
No packet received within timeout! - Good.
Test passed.
**********************
Test 3: /ff02:0:0:0:0:0:0:a
Join: /ff02:0:0:0:0:0:0:a
Send packet to: /ff02:0:0:0:0:0:0:a
Got packet! - Good.
Send packet to: /ff02:0:0:0:0:0:0:a
Got packet! - Good.
Leave: /ff02:0:0:0:0:0:0:a
Failed: Got packet after leaving group!!!
Join: /ff02:0:0:0:0:0:0:a
Send packet to: /ff02:0:0:0:0:0:0:a
Got packet! - Good.
Send packet to: /ff02:0:0:0:0:0:0:a
Got packet! - Good.
Leave: /ff02:0:0:0:0:0:0:a
Failed: Got packet after leaving group!!!
Test failed!!
**********************
3 test(s) executed. 1 test(s) failed.
----------System.err:(12/706)----------
java.lang.Exception: Test failed - see log file for details
at Test.main(Test.java:211)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:569)
at com.sun.javatest.regtest.agent.MainActionHelper$SameVMRunnable.run(MainActionHelper.java:229)
at java.base/java.lang.Thread.run(Thread.java:831)