diff --git a/player.c b/player.c
index 7560bfb4..c3b74267 100644
--- a/player.c
+++ b/player.c
@@ -1659,8 +1659,6 @@ static void *player_thread_func(void *arg) {
   player_volume(config.airplay_volume, conn);
   int64_t frames_to_drop = 0;
   // debug(1, "Play begin");
-  if (play_number % 100 == 0)
-    debug(3, "Play frame %d.", play_number);
   while (!conn->player_thread_please_stop) {
     abuf_t *inframe = buffer_get_frame(conn);
     if (inframe) {
@@ -1668,9 +1666,11 @@ static void *player_thread_func(void *arg) {
       inbuflength = inframe->length;
       if (inbuf) {
         play_number++;
+        if (play_number % 100 == 0)
+          debug(3, "Play frame %d.", play_number);
         conn->play_number_after_flush++;
         if (inframe->timestamp == 0) {
-          // debug(1,"Player has a supplied silent frame.");
+          debug(3, "Player has a supplied silent frame.");
           conn->last_seqno_read = (SUCCESSOR(conn->last_seqno_read) &
                                    0xffff); // manage the packet out of sequence minder
           config.output->play(silence, conn->max_frames_per_packet * conn->output_sample_ratio);
@@ -1685,7 +1685,9 @@ static void *player_thread_func(void *arg) {
           */
           config.output->play(silence, conn->max_frames_per_packet * conn->output_sample_ratio);
         } else if (frames_to_drop) {
-          // debug(2,"%lld frames to drop.",frames_to_drop);
+          if (frames_to_drop > 3 * config.output_rate)
+            warn("Very large number of frames to drop: %" PRId64 ".");
+          debug(3, "%" PRId64 " frames to drop.", frames_to_drop);
           frames_to_drop -= inframe->length;
           if (frames_to_drop < 0)
             frames_to_drop = 0;
@@ -1885,6 +1887,9 @@ static void *player_thread_func(void *arg) {
             if ((config.no_sync == 0) && (inframe->timestamp != 0) &&
                 (!conn->player_thread_please_stop) && (config.resyncthreshold > 0.0) &&
                 (abs_sync_error > config.resyncthreshold * config.output_rate)) {
+              if (abs_sync_error > 3 * config.output_rate) {
+                warn("The sync error is very large: %" PRId64 " frames.");
+              }
               sync_error_out_of_bounds++;
             } else {
               sync_error_out_of_bounds = 0;
diff --git a/player.h b/player.h
index 4ceabf9c..6f1a8b5b 100644
--- a/player.h
+++ b/player.h
@@ -141,6 +141,12 @@ typedef struct {
   int control_socket;                 // our local [server] control socket
   int timing_socket;                  // local timing socket
 
+  uint16_t remote_control_port;
+  uint16_t remote_timing_port;
+  uint16_t local_audio_port;
+  uint16_t local_control_port;
+  uint16_t local_timing_port;
+
   int64_t latency_delayed_timestamp; // this is for debugging only...
   int64_t reference_timestamp;
   uint64_t reference_timestamp_time;
diff --git a/rtp.c b/rtp.c
index 5b88c3af..8168de14 100644
--- a/rtp.c
+++ b/rtp.c
@@ -691,9 +691,10 @@ void *rtp_timing_receiver(void *arg) {
   return NULL;
 }
 
-static int bind_port(int ip_family, const char *self_ip_address, uint32_t scope_id, int *sock) {
+static uint16_t bind_port(int ip_family, const char *self_ip_address, uint32_t scope_id,
+                          int *sock) {
   // look for a port in the range, if any was specified.
-  int desired_port = config.udp_port_base;
+  uint16_t desired_port = config.udp_port_base;
   int ret;
 
   int local_socket = socket(ip_family, SOCK_DGRAM, IPPROTO_UDP);
@@ -731,7 +732,7 @@ static int bind_port(int ip_family, const char *self_ip_address, uint32_t scope_
         "check for restrictive firewall settings or a bad router!");
   }
 
-  int sport;
+  uint16_t sport;
   SOCKADDR local;
   socklen_t local_len = sizeof(local);
   getsockname(local_socket, (struct sockaddr *)&local, &local_len);
@@ -751,123 +752,128 @@ static int bind_port(int ip_family, const char *self_ip_address, uint32_t scope_
   return sport;
 }
 
-void rtp_setup(SOCKADDR *local, SOCKADDR *remote, int cport, int tport, int *lsport, int *lcport,
-               int *ltport, rtsp_conn_info *conn) {
+void rtp_setup(SOCKADDR *local, SOCKADDR *remote, uint16_t cport, uint16_t tport,
+               rtsp_conn_info *conn) {
 
   // this gets the local and remote ip numbers (and ports used for the TCD stuff)
   // we use the local stuff to specify the address we are coming from and
   // we use the remote stuff to specify where we're goint to
 
   if (conn->rtp_running)
-    die("rtp_setup called with active stream!");
+    warn("rtp_setup has been called with al already-active stream -- ignored. Possible duplicate "
+         "SETUP call?");
+  else {
 
-  debug(2, "rtp_setup: cport=%d tport=%d.", cport, tport);
+    debug(2, "rtp_setup: cport=%d tport=%d.", cport, tport);
 
-  // print out what we know about the client
-  void *client_addr = NULL, *self_addr = NULL;
-  // int client_port, self_port;
-  // char client_port_str[64];
-  // char self_addr_str[64];
+    // print out what we know about the client
+    void *client_addr = NULL, *self_addr = NULL;
+    // int client_port, self_port;
+    // char client_port_str[64];
+    // char self_addr_str[64];
 
-  conn->connection_ip_family =
-      remote->SAFAMILY; // keep information about the kind of ip of the client
+    conn->connection_ip_family =
+        remote->SAFAMILY; // keep information about the kind of ip of the client
 
 #ifdef AF_INET6
-  if (conn->connection_ip_family == AF_INET6) {
-    struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)remote;
-    client_addr = &(sa6->sin6_addr);
-    // client_port = ntohs(sa6->sin6_port);
-    sa6 = (struct sockaddr_in6 *)local;
-    self_addr = &(sa6->sin6_addr);
-    // self_port = ntohs(sa6->sin6_port);
-    conn->self_scope_id = sa6->sin6_scope_id;
-  }
+    if (conn->connection_ip_family == AF_INET6) {
+      struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)remote;
+      client_addr = &(sa6->sin6_addr);
+      // client_port = ntohs(sa6->sin6_port);
+      sa6 = (struct sockaddr_in6 *)local;
+      self_addr = &(sa6->sin6_addr);
+      // self_port = ntohs(sa6->sin6_port);
+      conn->self_scope_id = sa6->sin6_scope_id;
+    }
 #endif
-  if (conn->connection_ip_family == AF_INET) {
-    struct sockaddr_in *sa4 = (struct sockaddr_in *)remote;
-    client_addr = &(sa4->sin_addr);
-    // client_port = ntohs(sa4->sin_port);
-    sa4 = (struct sockaddr_in *)local;
-    self_addr = &(sa4->sin_addr);
-    // self_port = ntohs(sa4->sin_port);
-  }
+    if (conn->connection_ip_family == AF_INET) {
+      struct sockaddr_in *sa4 = (struct sockaddr_in *)remote;
+      client_addr = &(sa4->sin_addr);
+      // client_port = ntohs(sa4->sin_port);
+      sa4 = (struct sockaddr_in *)local;
+      self_addr = &(sa4->sin_addr);
+      // self_port = ntohs(sa4->sin_port);
+    }
 
-  inet_ntop(conn->connection_ip_family, client_addr, conn->client_ip_string,
-            sizeof(conn->client_ip_string));
-  inet_ntop(conn->connection_ip_family, self_addr, conn->self_ip_string,
-            sizeof(conn->self_ip_string));
+    inet_ntop(conn->connection_ip_family, client_addr, conn->client_ip_string,
+              sizeof(conn->client_ip_string));
+    inet_ntop(conn->connection_ip_family, self_addr, conn->self_ip_string,
+              sizeof(conn->self_ip_string));
 
-  debug(2, "Set up play connection from %s to self at %s on RTSP conversation thread %d.",
-        conn->client_ip_string, conn->self_ip_string, conn->connection_number);
+    debug(2, "Set up play connection from %s to self at %s on RTSP conversation thread %d.",
+          conn->client_ip_string, conn->self_ip_string, conn->connection_number);
 
-  // set up a the record of the remote's control socket
-  struct addrinfo hints;
-  struct addrinfo *servinfo;
+    // set up a the record of the remote's control socket
+    struct addrinfo hints;
+    struct addrinfo *servinfo;
 
-  memset(&conn->rtp_client_control_socket, 0, sizeof(conn->rtp_client_control_socket));
-  memset(&hints, 0, sizeof hints);
-  hints.ai_family = conn->connection_ip_family;
-  hints.ai_socktype = SOCK_DGRAM;
-  char portstr[20];
-  snprintf(portstr, 20, "%d", cport);
-  if (getaddrinfo(conn->client_ip_string, portstr, &hints, &servinfo) != 0)
-    die("Can't get address of client's control port");
+    memset(&conn->rtp_client_control_socket, 0, sizeof(conn->rtp_client_control_socket));
+    memset(&hints, 0, sizeof hints);
+    hints.ai_family = conn->connection_ip_family;
+    hints.ai_socktype = SOCK_DGRAM;
+    char portstr[20];
+    snprintf(portstr, 20, "%d", cport);
+    if (getaddrinfo(conn->client_ip_string, portstr, &hints, &servinfo) != 0)
+      die("Can't get address of client's control port");
 
 #ifdef AF_INET6
-  if (servinfo->ai_family == AF_INET6) {
-    memcpy(&conn->rtp_client_control_socket, servinfo->ai_addr, sizeof(struct sockaddr_in6));
-    // ensure the scope id matches that of remote. this is needed for link-local addresses.
-    struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)&conn->rtp_client_control_socket;
-    sa6->sin6_scope_id = conn->self_scope_id;
-  } else
+    if (servinfo->ai_family == AF_INET6) {
+      memcpy(&conn->rtp_client_control_socket, servinfo->ai_addr, sizeof(struct sockaddr_in6));
+      // ensure the scope id matches that of remote. this is needed for link-local addresses.
+      struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)&conn->rtp_client_control_socket;
+      sa6->sin6_scope_id = conn->self_scope_id;
+    } else
 #endif
-    memcpy(&conn->rtp_client_control_socket, servinfo->ai_addr, sizeof(struct sockaddr_in));
-  freeaddrinfo(servinfo);
+      memcpy(&conn->rtp_client_control_socket, servinfo->ai_addr, sizeof(struct sockaddr_in));
+    freeaddrinfo(servinfo);
 
-  // set up a the record of the remote's timing socket
-  memset(&conn->rtp_client_timing_socket, 0, sizeof(conn->rtp_client_timing_socket));
-  memset(&hints, 0, sizeof hints);
-  hints.ai_family = conn->connection_ip_family;
-  hints.ai_socktype = SOCK_DGRAM;
-  snprintf(portstr, 20, "%d", tport);
-  if (getaddrinfo(conn->client_ip_string, portstr, &hints, &servinfo) != 0)
-    die("Can't get address of client's timing port");
+    // set up a the record of the remote's timing socket
+    memset(&conn->rtp_client_timing_socket, 0, sizeof(conn->rtp_client_timing_socket));
+    memset(&hints, 0, sizeof hints);
+    hints.ai_family = conn->connection_ip_family;
+    hints.ai_socktype = SOCK_DGRAM;
+    snprintf(portstr, 20, "%d", tport);
+    if (getaddrinfo(conn->client_ip_string, portstr, &hints, &servinfo) != 0)
+      die("Can't get address of client's timing port");
 #ifdef AF_INET6
-  if (servinfo->ai_family == AF_INET6) {
-    memcpy(&conn->rtp_client_timing_socket, servinfo->ai_addr, sizeof(struct sockaddr_in6));
-    // ensure the scope id matches that of remote. this is needed for link-local addresses.
-    struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)&conn->rtp_client_timing_socket;
-    sa6->sin6_scope_id = conn->self_scope_id;
-  } else
+    if (servinfo->ai_family == AF_INET6) {
+      memcpy(&conn->rtp_client_timing_socket, servinfo->ai_addr, sizeof(struct sockaddr_in6));
+      // ensure the scope id matches that of remote. this is needed for link-local addresses.
+      struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)&conn->rtp_client_timing_socket;
+      sa6->sin6_scope_id = conn->self_scope_id;
+    } else
 #endif
-    memcpy(&conn->rtp_client_timing_socket, servinfo->ai_addr, sizeof(struct sockaddr_in));
-  freeaddrinfo(servinfo);
+      memcpy(&conn->rtp_client_timing_socket, servinfo->ai_addr, sizeof(struct sockaddr_in));
+    freeaddrinfo(servinfo);
 
-  // now, we open three sockets -- one for the audio stream, one for the timing and one for the
-  // control
+    // now, we open three sockets -- one for the audio stream, one for the timing and one for the
+    // control
+    conn->remote_control_port = cport;
+    conn->remote_timing_port = tport;
 
-  *lsport = bind_port(conn->connection_ip_family, conn->self_ip_string, conn->self_scope_id,
-                      &conn->audio_socket);
-  *lcport = bind_port(conn->connection_ip_family, conn->self_ip_string, conn->self_scope_id,
-                      &conn->control_socket);
-  *ltport = bind_port(conn->connection_ip_family, conn->self_ip_string, conn->self_scope_id,
-                      &conn->timing_socket);
+    conn->local_audio_port = bind_port(conn->connection_ip_family, conn->self_ip_string,
+                                       conn->self_scope_id, &conn->audio_socket);
+    conn->local_control_port = bind_port(conn->connection_ip_family, conn->self_ip_string,
+                                         conn->self_scope_id, &conn->control_socket);
+    conn->local_timing_port = bind_port(conn->connection_ip_family, conn->self_ip_string,
+                                        conn->self_scope_id, &conn->timing_socket);
 
-  debug(2, "listening for audio, control and timing on ports %d, %d, %d.", *lsport, *lcport,
-        *ltport);
+    debug(2, "listening for audio, control and timing on ports %d, %d, %d.", conn->local_audio_port,
+          conn->local_control_port, conn->local_timing_port);
 
-  conn->reference_timestamp = 0;
-  // pthread_create(&rtp_audio_thread, NULL, &rtp_audio_receiver, NULL);
-  // pthread_create(&rtp_control_thread, NULL, &rtp_control_receiver, NULL);
-  // pthread_create(&rtp_timing_thread, NULL, &rtp_timing_receiver, NULL);
+    conn->reference_timestamp = 0;
+    // pthread_create(&rtp_audio_thread, NULL, &rtp_audio_receiver, NULL);
+    // pthread_create(&rtp_control_thread, NULL, &rtp_control_receiver, NULL);
+    // pthread_create(&rtp_timing_thread, NULL, &rtp_timing_receiver, NULL);
 
-  conn->request_sent = 0;
-  conn->rtp_running = 1;
+    conn->request_sent = 0;
+    conn->rtp_running = 1;
 
 #ifdef CONFIG_METADATA
-  send_ssnc_metadata('clip', strdup(conn->client_ip_string), strlen(conn->client_ip_string), 1);
-  send_ssnc_metadata('svip', strdup(conn->self_ip_string), strlen(conn->self_ip_string), 1);
+    send_ssnc_metadata('clip', strdup(conn->client_ip_string), strlen(conn->client_ip_string), 1);
+    send_ssnc_metadata('svip', strdup(conn->self_ip_string), strlen(conn->self_ip_string), 1);
 #endif
+  }
 }
 
 void get_reference_timestamp_stuff(int64_t *timestamp, uint64_t *timestamp_time,
diff --git a/rtp.h b/rtp.h
index c89f7e56..743cff52 100644
--- a/rtp.h
+++ b/rtp.h
@@ -12,8 +12,7 @@ void *rtp_audio_receiver(void *arg);
 void *rtp_control_receiver(void *arg);
 void *rtp_timing_receiver(void *arg);
 
-void rtp_setup(SOCKADDR *local, SOCKADDR *remote, int controlport, int timingport,
-               int *local_server_port, int *local_control_port, int *local_timing_port,
+void rtp_setup(SOCKADDR *local, SOCKADDR *remote, uint16_t controlport, uint16_t timingport,
                rtsp_conn_info *conn);
 void rtp_request_resend(seq_t first, uint32_t count, rtsp_conn_info *conn);
 void rtp_request_client_pause(rtsp_conn_info *conn); // ask the client to pause
diff --git a/rtsp.c b/rtsp.c
index 32fe548d..b874bfe7 100644
--- a/rtsp.c
+++ b/rtsp.c
@@ -668,7 +668,10 @@ static void msg_write_response(int fd, rtsp_message *resp) {
 static void handle_record(rtsp_conn_info *conn, rtsp_message *req, rtsp_message *resp) {
   debug(2, "Connection %d: RECORD", conn->connection_number);
 
-  player_play(conn); // the thread better be 0
+  if (conn->player_thread)
+    warn("Duplicate RECORD message -- ignored");
+  else
+    player_play(conn); // the thread better be 0
 
   resp->respcode = 200;
   // I think this is for telling the client what the absolute minimum latency
@@ -700,7 +703,6 @@ static void handle_record(rtsp_conn_info *conn, rtsp_message *req, rtsp_message
       }
     }
   }
-  // usleep(500000);
 }
 
 static void handle_options(rtsp_conn_info *conn, __attribute__((unused)) rtsp_message *req,
@@ -724,11 +726,9 @@ static void handle_teardown(rtsp_conn_info *conn, __attribute__((unused)) rtsp_m
   debug(3,
         "TEARDOWN: synchronously terminating the player thread of RTSP conversation thread %d (2).",
         conn->connection_number);
-  // if (rtsp_playing()) {
   player_stop(conn);
   debug(3, "TEARDOWN: successful termination of playing thread of RTSP conversation thread %d.",
         conn->connection_number);
-  //}
 }
 
 static void handle_flush(rtsp_conn_info *conn, rtsp_message *req, rtsp_message *resp) {
@@ -763,8 +763,7 @@ static void handle_flush(rtsp_conn_info *conn, rtsp_message *req, rtsp_message *
 
 static void handle_setup(rtsp_conn_info *conn, rtsp_message *req, rtsp_message *resp) {
   debug(2, "Connection %d: SETUP", conn->connection_number);
-  int cport, tport;
-  int lsport, lcport, ltport;
+  uint16_t cport, tport;
 
   char *ar = msg_get_header(req, "Active-Remote");
   if (ar) {
@@ -787,48 +786,52 @@ static void handle_setup(rtsp_conn_info *conn, rtsp_message *req, rtsp_message *
   }
 
   char *hdr = msg_get_header(req, "Transport");
-  if (!hdr)
+  if (!hdr) {
+    debug(1, "SETUP doesn't contain a Transport header.");
     goto error;
+  }
 
   char *p;
   p = strstr(hdr, "control_port=");
-  if (!p)
+  if (!p) {
+    debug(1, "SETUP doesn't specify a control_port.");
     goto error;
+  }
   p = strchr(p, '=') + 1;
   cport = atoi(p);
 
   p = strstr(hdr, "timing_port=");
-  if (!p)
+  if (!p) {
+    debug(1, "SETUP doesn't specify a timing_port.");
     goto error;
+  }
   p = strchr(p, '=') + 1;
   tport = atoi(p);
 
-  //  rtsp_take_player();
-  rtp_setup(&conn->local, &conn->remote, cport, tport, &lsport, &lcport, &ltport, conn);
-  if (!lsport)
-    goto error;
-  char *q;
-  p = strstr(hdr, "control_port=");
-  if (p) {
-    q = strchr(p, ';'); // get past the control port entry
-    *p++ = 0;
-    if (q++)
-      strcat(hdr, q); // should unsplice the control port entry
+  if (conn->rtp_running) {
+    if ((conn->remote_control_port != cport) || (conn->remote_timing_port != tport)) {
+      warn("Duplicate SETUP message with different control (old %u, new %u) or timing (old %u, new "
+           "%u) ports! This is probably fatal!",
+           conn->remote_control_port, cport, conn->remote_timing_port, tport);
+    } else {
+      warn("Duplicate SETUP message with the same control (%u) and timing (%u) ports. This is "
+           "probably not fatal.",
+           conn->remote_control_port, conn->remote_timing_port);
+    }
+  } else {
+    rtp_setup(&conn->local, &conn->remote, cport, tport, conn);
   }
-  p = strstr(hdr, "timing_port=");
-  if (p) {
-    q = strchr(p, ';'); // get past the timing port entry
-    *p++ = 0;
-    if (q++)
-      strcat(hdr, q); // should unsplice the timing port entry
+  if (conn->local_audio_port == 0) {
+    debug(1, "SETUP seems to specify a null audio port.");
+    goto error;
   }
 
   char resphdr[256] = "";
   snprintf(resphdr, sizeof(resphdr), "RTP/AVP/"
-                   "UDP;unicast;interleaved=0-1;mode=record;control_port=%d;"
-                   "timing_port=%d;server_"
-                   "port=%d",
-          lcport, ltport, lsport);
+                                     "UDP;unicast;interleaved=0-1;mode=record;control_port=%d;"
+                                     "timing_port=%d;server_"
+                                     "port=%d",
+           conn->local_control_port, conn->local_timing_port, conn->local_audio_port);
 
   msg_add_header(resp, "Transport", resphdr);
 
@@ -1435,7 +1438,7 @@ static void handle_announce(rtsp_conn_info *conn, rtsp_message *req, rtsp_messag
     have_the_player = 1;
   } else if ((playing_conn) &&
              (playing_conn->connection_number == conn->connection_number)) { // duplicate ANNOUNCE
-    debug(1, "Duplicate ANNOUNCE, by the look of it!");
+    warn("Duplicate ANNOUNCE, by the look of it!");
     have_the_player = 1;
   } else {
     int should_wait = 0;