diff --git a/src/host/dmr/Slot.cpp b/src/host/dmr/Slot.cpp
index e20ac161..3db629ea 100644
--- a/src/host/dmr/Slot.cpp
+++ b/src/host/dmr/Slot.cpp
@@ -482,7 +482,8 @@ void Slot::clock()
         m_adjSiteUpdate.clock(ms);
         if (m_adjSiteUpdate.isRunning() && m_adjSiteUpdate.hasExpired()) {
             if (m_rfState == RS_RF_LISTENING && m_netState == RS_NET_IDLE) {
-                m_network->announceAffiliationUpdate(m_affiliations->grpAffTable());
+                if (m_network != nullptr)
+                    m_network->announceAffiliationUpdate(m_affiliations->grpAffTable());
                 m_adjSiteUpdate.start();
             }
         }
diff --git a/src/host/nxdn/Control.cpp b/src/host/nxdn/Control.cpp
index 4c448936..1c31a92d 100644
--- a/src/host/nxdn/Control.cpp
+++ b/src/host/nxdn/Control.cpp
@@ -567,7 +567,8 @@ void Control::clock(uint32_t ms)
         m_adjSiteUpdate.clock(ms);
         if (m_adjSiteUpdate.isRunning() && m_adjSiteUpdate.hasExpired()) {
             if (m_rfState == RS_RF_LISTENING && m_netState == RS_NET_IDLE) {
-                m_network->announceAffiliationUpdate(m_affiliations.grpAffTable());
+                if (m_network != nullptr)
+                    m_network->announceAffiliationUpdate(m_affiliations.grpAffTable());
                 m_adjSiteUpdate.start();
             }
         }
diff --git a/src/host/p25/Control.cpp b/src/host/p25/Control.cpp
index c1e96e39..e1b5a85e 100644
--- a/src/host/p25/Control.cpp
+++ b/src/host/p25/Control.cpp
@@ -819,7 +819,8 @@ void Control::clock(uint32_t ms)
         if (m_adjSiteUpdate.isRunning() && m_adjSiteUpdate.hasExpired()) {
             if (m_rfState == RS_RF_LISTENING && m_netState == RS_NET_IDLE) {
                 m_control->writeAdjSSNetwork();
-                m_network->announceAffiliationUpdate(m_affiliations.grpAffTable());
+                if (m_network != nullptr)
+                    m_network->announceAffiliationUpdate(m_affiliations.grpAffTable());
                 m_adjSiteUpdate.start();
             }
         }