diff --git a/libowlps-client/libowlps-client.c b/libowlps-client/libowlps-client.c
index 6def3f0..29b2d59 100644
--- a/libowlps-client/libowlps-client.c
+++ b/libowlps-client/libowlps-client.c
@@ -104,8 +104,8 @@ void owl_send_request(const int sockfd,
       owl_msleep(delay) ; // Wait during the wanted delay
       if (! owl_run)
         break ;
-      memcpy(&((char*) packet)[packet_size - sizeof(uint16_t)],
-             &current_pkt, sizeof(uint16_t)) ;
+      // Update the packet number:
+      memcpy(&((char*) packet)[1], &current_pkt, sizeof(uint16_t)) ;
       owl_send_packet(sockfd, server, packet, packet_size) ;
     }
 
diff --git a/owlps-client/owlps-client.c b/owlps-client/owlps-client.c
index 6d4dd81..70d15c8 100644
--- a/owlps-client/owlps-client.c
+++ b/owlps-client/owlps-client.c
@@ -460,6 +460,14 @@ void make_packet()
 
       // Packet type:
       memset(&packet[offset++], OWL_REQUEST_CALIBRATION, 1) ;
+      // Number of the current packet (1 for the first):
+      npkt = htons(1u) ;
+      memcpy(&packet[offset], &npkt, sizeof(uint16_t)) ;
+      offset += sizeof(uint16_t) ;
+      // Number of packets:
+      npkt = htons(options.nb_pkt) ;
+      memcpy(&packet[offset], &npkt, sizeof(uint16_t)) ;
+      offset += sizeof(uint16_t) ;
       // Request time:
       memcpy(&packet[offset], &request_time, sizeof(request_time)) ;
       offset += sizeof(request_time) ;
@@ -479,19 +487,11 @@ void make_packet()
       memcpy(&packet[offset], &options.y, sizeof(float)) ;
       offset += sizeof(float) ;
       memcpy(&packet[offset], &options.z, sizeof(float)) ;
-      offset += sizeof(float) ;
       // Convert the coordinates back to the host endianess (mandatory
       // in flood mode):
       options.x = owl_ntohf(options.x) ;
       options.y = owl_ntohf(options.y) ;
       options.z = owl_ntohf(options.z) ;
-      // Number of packets:
-      npkt = htons(options.nb_pkt) ;
-      memcpy(&packet[offset], &npkt, sizeof(uint16_t)) ;
-      offset += sizeof(uint16_t) ;
-      // Number of the current packet (1 for the first):
-      npkt = htons(1u) ;
-      memcpy(&packet[offset], &npkt, sizeof(uint16_t)) ;
     }
 
   else // Standard packet
@@ -505,16 +505,16 @@ void make_packet()
 
       // Packet type:
       memset(&packet[offset++], OWL_REQUEST_NORMAL, 1) ;
-      // Request time:
-      memcpy(&packet[offset], &request_time, sizeof(request_time)) ;
-      offset += sizeof(request_time) ;
+      // Number of the current packet (1 for the first):
+      npkt = htons(1u) ;
+      memcpy(&packet[offset], &npkt, sizeof(uint16_t)) ;
+      offset += sizeof(uint16_t) ;
       // Number of packets:
       npkt = htons(options.nb_pkt) ;
       memcpy(&packet[offset], &npkt, sizeof(uint16_t)) ;
       offset += sizeof(uint16_t) ;
-      // Number of the current packet (1 for the first):
-      npkt = htons(1u) ;
-      memcpy(&packet[offset], &npkt, sizeof(uint16_t)) ;
+      // Request time:
+      memcpy(&packet[offset], &request_time, sizeof(request_time)) ;
     }
 
   printf("Packet timestamp: %s\n", request_time_str) ;
diff --git a/owlps-listener/owlps-listenerd.c b/owlps-listener/owlps-listenerd.c
index f75fd53..3e5bc94 100644
--- a/owlps-listener/owlps-listenerd.c
+++ b/owlps-listener/owlps-listenerd.c
@@ -1494,6 +1494,14 @@ uint_fast16_t make_packet(uint8_t **packet)
 
   // Request type:
   memset(&pkt[offset++], OWL_REQUEST_AUTOCALIBRATION, 1) ;
+  // Number of the current packet (1 for the first):
+  npkt = htons(1u) ;
+  memcpy(&pkt[offset], &npkt, sizeof(uint16_t)) ;
+  offset += sizeof(uint16_t) ;
+  // Number of packets:
+  npkt = htons(GET_AUTOCALIBRATION_NBPKT()) ;
+  memcpy(&pkt[offset], &npkt, sizeof(uint16_t)) ;
+  offset += sizeof(uint16_t) ;
   // Timestamp:
   memcpy(&pkt[offset], &request_time, sizeof(request_time)) ;
   offset += sizeof(request_time) ;
@@ -1504,16 +1512,8 @@ uint_fast16_t make_packet(uint8_t **packet)
   memcpy(&pkt[offset], &my_position_y, sizeof(float)) ;
   offset += sizeof(float) ;
   memcpy(&pkt[offset], &my_position_z, sizeof(float)) ;
-  offset += sizeof(float) ;
-  // Number of packets:
-  npkt = htons(GET_AUTOCALIBRATION_NBPKT()) ;
-  memcpy(&pkt[offset], &npkt, sizeof(uint16_t)) ;
-  offset += sizeof(uint16_t) ;
-  // Number of the current packet (1 for the first):
-  npkt = htons(1u) ;
-  memcpy(&pkt[offset], &npkt, sizeof(uint16_t)) ;
 #ifndef NDEBUG
-  offset += sizeof(uint16_t) ;
+  offset += sizeof(float) ;
   assert(offset == size) ;
 #endif // NDEBUG