diff --git a/src/hci.c b/src/hci.c
index 74702bfd0..8317157e0 100644
--- a/src/hci.c
+++ b/src/hci.c
@@ -4628,7 +4628,7 @@ static void sco_handler(uint8_t * packet, uint16_t size){
 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
     // propagate ISO packets received as ACL
-    hci_iso_stream_t * iso_stream;
+    hci_iso_stream_t * iso_stream = NULL;
     if ((packet_type == HCI_ACL_DATA_PACKET) && (size >= HCI_ACL_HEADER_SIZE)){
         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
         iso_stream = hci_iso_stream_for_con_handle(con_handle);