IllegalStateException during service unregistration

ERROR: Bundle org.apache.felix.metatype [75] EventDispatcher: Error during dispatch. (java.lang.IllegalStateException: Invalid BundleContext.)
java.lang.IllegalStateException: Invalid BundleContext.
	at org.apache.felix.framework.BundleContextImpl.checkValidity(BundleContextImpl.java:517)
	at org.apache.felix.framework.BundleContextImpl.ungetService(BundleContextImpl.java:475)
	at org.apache.felix.metatype.internal.MetaTypeProviderTracker.removedService(MetaTypeProviderTracker.java:60)
	at org.osgi.util.tracker.ServiceTracker$Tracked.customizerRemoved(ServiceTracker.java:956)
	at org.osgi.util.tracker.ServiceTracker$Tracked.customizerRemoved(ServiceTracker.java:864)
	at org.osgi.util.tracker.AbstractTracked.untrack(AbstractTracked.java:341)
	at org.osgi.util.tracker.ServiceTracker$Tracked.serviceChanged(ServiceTracker.java:902)
	at org.apache.felix.framework.util.EventDispatcher.invokeServiceListenerCallback(EventDispatcher.java:934)
	at org.apache.felix.framework.util.EventDispatcher.fireEventImmediately(EventDispatcher.java:795)
	at org.apache.felix.framework.util.EventDispatcher.fireServiceEvent(EventDispatcher.java:544)
	at org.apache.felix.framework.Felix.fireServiceEvent(Felix.java:4666)
	at org.apache.felix.framework.Felix.access$000(Felix.java:95)
	at org.apache.felix.framework.Felix$1.serviceChanged(Felix.java:422)
	at org.apache.felix.framework.ServiceRegistry.unregisterService(ServiceRegistry.java:162)
	at org.apache.felix.framework.ServiceRegistrationImpl.unregister(ServiceRegistrationImpl.java:141)
	at org.apache.felix.eventadmin.impl.Configuration.destroy(Configuration.java:355)
	at org.apache.felix.eventadmin.impl.Activator.stop(Activator.java:83)
	at org.apache.felix.framework.util.SecureAction.stopActivator(SecureAction.java:667)
	at org.apache.felix.framework.Felix.stopBundle(Felix.java:2777)
	at org.apache.felix.framework.Felix.updateBundle(Felix.java:2509)
	at org.apache.felix.framework.BundleImpl.update(BundleImpl.java:973)
	at org.apache.felix.framework.BundleImpl.update(BundleImpl.java:960)
	at org.apache.karaf.shell.dev.LoadTest$1.run(LoadTest.java:93)