diff --git a/src/ranap_msg_factory.c b/src/ranap_msg_factory.c
index 16a9d032..cd2ddfc6 100644
--- a/src/ranap_msg_factory.c
+++ b/src/ranap_msg_factory.c
@@ -588,6 +588,14 @@ static RANAP_RAB_Parameters_t *new_rab_par_voice(void)
 	return rab;
 }
 
+static RANAP_NAS_SynchronisationIndicator_t *new_rab_nas_sync_ind(int val)
+{
+	uint8_t val_buf = (val / 10) << 4;
+	RANAP_NAS_SynchronisationIndicator_t *nsi = CALLOC(1, sizeof(*nsi));
+	BIT_STRING_fromBuf(nsi, &val_buf, 4);
+	return nsi;
+}
+
 static RANAP_RAB_Parameters_t *new_rab_par_data(uint32_t dl_max_bitrate, uint32_t ul_max_bitrate)
 {
 	RANAP_RAB_Parameters_t *rab = CALLOC(1, sizeof(*rab));
@@ -729,7 +737,7 @@ struct msgb *ranap_new_msg_rab_assign_voice(uint8_t rab_id, uint32_t rtp_ip,
 	RANAP_RAB_SetupOrModifyItemFirst_t first;
 	memset(&first, 0, sizeof(first));
 	assign_new_ra_id(&first.rAB_ID, rab_id);
-	//first.nAS_SynchronisationIndicator = FIXME;
+	first.nAS_SynchronisationIndicator = new_rab_nas_sync_ind(60);
 	first.rAB_Parameters = new_rab_par_voice();
 	first.userPlaneInformation = new_upi(RANAP_UserPlaneMode_support_mode_for_predefined_SDU_sizes, 1); /* 2? */
 	first.transportLayerInformation = new_transp_info_rtp(rtp_ip, rtp_port,
diff --git a/src/tests/test-ranap.ok b/src/tests/test-ranap.ok
index bda3c8ee..dc959eb3 100644
--- a/src/tests/test-ranap.ok
+++ b/src/tests/test-ranap.ok
@@ -88,10 +88,10 @@ Decoded Cause Misc=115
     <id>53</id>
     <firstCriticality><reject/></firstCriticality>
     <firstValue>
-        38 02 D8 01 2F A7 20 2F A8 00 00 F4 4C 08 0A 02 
-        80 00 51 40 00 27 20 28 14 00 67 40 00 00 22 28 
-        14 00 3C 40 00 00 00 50 3D 02 00 02 0D C0 35 00 
-        01 0A 0B 0C 0D 40 09 26 00 00
+        78 02 CD 80 10 2F A7 20 2F A8 00 00 F4 4C 08 0A 
+        02 80 00 51 40 00 27 20 28 14 00 67 40 00 00 22 
+        28 14 00 3C 40 00 00 00 50 3D 02 00 02 0D C0 35 
+        00 01 0A 0B 0C 0D 40 09 26 00 00
     </firstValue>
     <secondCriticality><ignore/></secondCriticality>
     <secondValue>00</secondValue>
@@ -100,14 +100,14 @@ Decoded Cause Misc=115
     <id>54</id>
     <criticality><ignore/></criticality>
     <value>
-        00 00 01 00 35 00 3A 38 02 D8 01 2F A7 20 2F A8 
-        00 00 F4 4C 08 0A 02 80 00 51 40 00 27 20 28 14 
-        00 67 40 00 00 22 28 14 00 3C 40 00 00 00 50 3D 
-        02 00 02 0D C0 35 00 01 0A 0B 0C 0D 40 09 26 00 
-        00 40 01 00
+        00 00 01 00 35 00 3B 78 02 CD 80 10 2F A7 20 2F 
+        A8 00 00 F4 4C 08 0A 02 80 00 51 40 00 27 20 28 
+        14 00 67 40 00 00 22 28 14 00 3C 40 00 00 00 50 
+        3D 02 00 02 0D C0 35 00 01 0A 0B 0C 0D 40 09 26 
+        00 00 40 01 00
     </value>
 </RANAP_IE>
-00 00 00 4b 00 00 01 00 36 40 44 00 00 01 00 35 00 3a 38 02 d8 01 2f a7 20 2f a8 00 00 f4 4c 08 0a 02 80 00 51 40 00 27 20 28 14 00 67 40 00 00 22 28 14 00 3c 40 00 00 00 50 3d 02 00 02 0d c0 35 00 01 0a 0b 0c 0d 40 09 26 00 00 40 01 00 
+00 00 00 4c 00 00 01 00 36 40 45 00 00 01 00 35 00 3b 78 02 cd 80 10 2f a7 20 2f a8 00 00 f4 4c 08 0a 02 80 00 51 40 00 27 20 28 14 00 67 40 00 00 22 28 14 00 3c 40 00 00 00 50 3d 02 00 02 0d c0 35 00 01 0a 0b 0c 0d 40 09 26 00 00 40 01 00 
 
 ==> RAB ASSIGNMENT COMMAND (DATA)
 <RANAP_ProtocolIE-FieldPair>