diff --git a/app/v4l2_to_ip/v4l2_to_ip.c b/app/v4l2_to_ip/v4l2_to_ip.c
index a98a33036..bc5dc9320 100644
--- a/app/v4l2_to_ip/v4l2_to_ip.c
+++ b/app/v4l2_to_ip/v4l2_to_ip.c
@@ -768,7 +768,11 @@ static void video_close(struct device* dev) {
 }
 
 static void video_log_status(struct device* dev) {
-  ioctl(dev->fd, VIDIOC_LOG_STATUS);
+  int ret;
+  ret = ioctl(dev->fd, VIDIOC_LOG_STATUS);
+  if (ret < 0) {
+    printf("Failed to log status: %s (%d).\n", strerror(errno), errno);
+  }
 }
 
 static int video_get_format(struct device* dev) {
diff --git a/lib/src/datapath/mt_shared_queue.c b/lib/src/datapath/mt_shared_queue.c
index e3e0ec45a..cb773098b 100644
--- a/lib/src/datapath/mt_shared_queue.c
+++ b/lib/src/datapath/mt_shared_queue.c
@@ -80,10 +80,10 @@ static int rsq_entry_free(struct mt_rsq_entry* entry) {
     mt_ring_dequeue_clean(entry->ring);
     rte_ring_free(entry->ring);
   }
-  if (entry->mcast_fd) {
-    close(entry->mcast_fd);
-    entry->mcast_fd = -1;
-  }
+  if (entry->mcast_fd > 0) close(entry->mcast_fd);
+
+  entry->mcast_fd = -1;
+
   info("%s(%d), succ on q %u idx %d\n", __func__, rsqm->port, entry->queue_id,
        entry->idx);
   mt_rte_free(entry);
diff --git a/lib/src/st2110/st_rx_video_session.c b/lib/src/st2110/st_rx_video_session.c
index 559a0807b..685fc069f 100644
--- a/lib/src/st2110/st_rx_video_session.c
+++ b/lib/src/st2110/st_rx_video_session.c
@@ -1325,14 +1325,9 @@ static int rv_start_pcap(struct st_rx_video_session_impl* s, enum mtl_session_po
     err("%s(%d,%d), pcap dump already started\n", __func__, idx, s_port);
     return -EIO;
   }
+  snprintf(pcap->file_name, sizeof(pcap->file_name), "st22rx_s%dp%d_%u_XXXXXX.pcapng",
+           idx, s_port, max_dump_packets);
 
-  if (s->st22_info) {
-    snprintf(pcap->file_name, sizeof(pcap->file_name), "st22rx_s%dp%d_%u_XXXXXX.pcapng",
-             idx, s_port, max_dump_packets);
-  } else {
-    snprintf(pcap->file_name, sizeof(pcap->file_name), "st22rx_s%dp%d_%u_XXXXXX.pcapng",
-             idx, s_port, max_dump_packets);
-  }
   int fd = mt_mkstemps(pcap->file_name, strlen(".pcapng"));
   if (fd < 0) {
     err("%s(%d,%d), failed to create pcap file %s\n", __func__, idx, s_port,
@@ -3337,7 +3332,8 @@ static int rv_migrate_dma(struct mtl_main_impl* impl,
 
 static void rv_stat(struct st_rx_video_sessions_mgr* mgr,
                     struct st_rx_video_session_impl* s) {
-  int m_idx = mgr ? mgr->idx : 0, idx = s->idx;
+  int m_idx = mgr->idx;
+  int idx = s->idx;
   uint64_t cur_time_ns = mt_get_monotonic_time();
   double time_sec = (double)(cur_time_ns - s->stat_last_time) / NS_PER_S;
   int frames_received = rte_atomic32_read(&s->stat_frames_received);
@@ -3560,6 +3556,7 @@ static int rvs_pkt_rx_tasklet_start(void* priv) {
 
 static int rv_detach(struct mtl_main_impl* impl, struct st_rx_video_sessions_mgr* mgr,
                      struct st_rx_video_session_impl* s) {
+  if (!mgr || !s) return -EINVAL;
   s->attached = false;
   rv_stat(mgr, s);
   rv_uinit(impl, s);
@@ -3776,6 +3773,8 @@ static int rv_sessions_stat(void* priv) {
   struct st_rx_video_sessions_mgr* mgr = priv;
   struct st_rx_video_session_impl* s;
 
+  if (!mgr) return -EINVAL;
+
   for (int j = 0; j < mgr->max_idx; j++) {
     s = rx_video_session_get_timeout(mgr, j, ST_SESSION_STAT_TIMEOUT_US);
     if (!s) continue;
diff --git a/manager/mtl_instance.hpp b/manager/mtl_instance.hpp
index 830860e80..5d9d17952 100644
--- a/manager/mtl_instance.hpp
+++ b/manager/mtl_instance.hpp
@@ -156,12 +156,16 @@ void mtl_instance::handle_message_get_lcore(mtl_lcore_message_t* lcore_msg) {
   uint16_t lcore_id = ntohs(lcore_msg->lcore);
   int ret = mtl_lcore::get_instance().get_lcore(lcore_id);
   if (ret < 0) {
-    send_response(ret);
+    if (send_response(ret) < 0) {
+      log(log_level::ERROR, "Failed to send response for get_lcore");
+    }
     return;
   }
   lcore_ids.insert(lcore_id);
   log(log_level::INFO, "Added lcore " + std::to_string(lcore_id));
-  send_response(0);
+  if (send_response(0) < 0) {
+    log(log_level::ERROR, "Failed to send response for get_lcore");
+  }
 }
 
 void mtl_instance::handle_message_put_lcore(mtl_lcore_message_t* lcore_msg) {
@@ -172,12 +176,16 @@ void mtl_instance::handle_message_put_lcore(mtl_lcore_message_t* lcore_msg) {
   uint16_t lcore_id = ntohs(lcore_msg->lcore);
   int ret = mtl_lcore::get_instance().put_lcore(lcore_id);
   if (ret < 0) {
-    send_response(ret);
+    if (send_response(ret) < 0) {
+      log(log_level::ERROR, "Failed to send response for put_lcore");
+    }
     return;
   }
   lcore_ids.erase(lcore_id);
   log(log_level::INFO, "Removed lcore " + std::to_string(lcore_id));
-  send_response(0);
+  if (send_response(0) < 0) {
+    log(log_level::ERROR, "Failed to send response for put_lcore");
+  }
 }
 
 void mtl_instance::handle_message_register(mtl_register_message_t* register_msg) {
@@ -190,7 +198,9 @@ void mtl_instance::handle_message_register(mtl_register_message_t* register_msg)
     auto interface = get_interface(ifindex);
     if (interface == nullptr) {
       log(log_level::ERROR, "Could not get interface " + std::to_string(ifindex));
-      send_response(-1);
+      if (send_response(-1) < 0) {
+        log(log_level::ERROR, "Failed to send response for register");
+      }
       return;
     }
   }
@@ -198,7 +208,9 @@ void mtl_instance::handle_message_register(mtl_register_message_t* register_msg)
   log(log_level::INFO, "Registered.");
 
   is_registered = true;
-  send_response(0);
+  if (send_response(0) < 0) {
+    log(log_level::ERROR, "Failed to send response for register");
+  }
 }
 
 std::shared_ptr<mtl_interface> mtl_instance::get_interface(const unsigned int ifindex) {
@@ -265,11 +277,15 @@ void mtl_instance::handle_message_udp_dp_filter(
   auto interface = get_interface(ifindex);
   if (interface == nullptr) {
     log(log_level::ERROR, "Failed to get interface " + std::to_string(ifindex));
-    send_response(-1);
+    if (send_response(-1) < 0) {
+      log(log_level::ERROR, "Failed to send response for udp_dp_filter");
+    }
     return;
   }
   int ret = interface->update_udp_dp_filter(port, add);
-  send_response(ret);
+  if (send_response(ret) < 0) {
+    log(log_level::ERROR, "Failed to send response for udp_dp_filter");
+  }
 }
 
 void mtl_instance::handle_message_if_get_queue(mtl_if_message_t* if_msg) {
@@ -277,12 +293,16 @@ void mtl_instance::handle_message_if_get_queue(mtl_if_message_t* if_msg) {
   auto interface = get_interface(ifindex);
   if (interface == nullptr) {
     log(log_level::ERROR, "Failed to get interface " + std::to_string(ifindex));
-    send_response(-1, MTL_MSG_TYPE_IF_QUEUE_ID);
+    if (send_response(-1, MTL_MSG_TYPE_IF_QUEUE_ID) < 0) {
+      log(log_level::ERROR, "Failed to send response for if_get_queue");
+    }
     return;
   }
   int ret = interface->get_queue();
   if (ret > 0) if_queue_ids[ifindex].insert(ret);
-  send_response(ret, MTL_MSG_TYPE_IF_QUEUE_ID);
+  if (send_response(ret, MTL_MSG_TYPE_IF_QUEUE_ID) < 0) {
+    log(log_level::ERROR, "Failed to send response for if_get_queue");
+  }
 }
 
 void mtl_instance::handle_message_if_put_queue(mtl_if_message_t* if_msg) {
@@ -290,13 +310,17 @@ void mtl_instance::handle_message_if_put_queue(mtl_if_message_t* if_msg) {
   auto interface = get_interface(ifindex);
   if (interface == nullptr) {
     log(log_level::ERROR, "Failed to get interface " + std::to_string(ifindex));
-    send_response(-1);
+    if (send_response(-1) < 0) {
+      log(log_level::ERROR, "Failed to send response for if_put_queue");
+    }
     return;
   }
   uint16_t queue_id = ntohs(if_msg->queue_id);
   int ret = interface->put_queue(queue_id);
   if (ret == 0) if_queue_ids[ifindex].erase(queue_id);
-  send_response(ret);
+  if (send_response(ret) < 0) {
+    log(log_level::ERROR, "Failed to send response for if_put_queue");
+  }
 }
 
 void mtl_instance::handle_message_if_add_flow(mtl_if_message_t* if_msg) {
@@ -304,14 +328,18 @@ void mtl_instance::handle_message_if_add_flow(mtl_if_message_t* if_msg) {
   auto interface = get_interface(ifindex);
   if (interface == nullptr) {
     log(log_level::ERROR, "Failed to get interface " + std::to_string(ifindex));
-    send_response(-1);
+    if (send_response(-1) < 0) {
+      log(log_level::ERROR, "Failed to send response for if_add_flow");
+    }
     return;
   }
   int ret = interface->add_flow(ntohs(if_msg->queue_id), ntohl(if_msg->flow_type),
                                 ntohl(if_msg->src_ip), ntohl(if_msg->dst_ip),
                                 ntohs(if_msg->src_port), ntohs(if_msg->dst_port));
   if (ret > 0) if_flow_ids[ifindex].insert(ret);
-  send_response(ret, MTL_MSG_TYPE_IF_FLOW_ID);
+  if (send_response(ret, MTL_MSG_TYPE_IF_FLOW_ID) < 0) {
+    log(log_level::ERROR, "Failed to send response for if_add_flow");
+  }
 }
 
 void mtl_instance::handle_message_if_del_flow(mtl_if_message_t* if_msg) {
@@ -319,13 +347,17 @@ void mtl_instance::handle_message_if_del_flow(mtl_if_message_t* if_msg) {
   auto interface = get_interface(ifindex);
   if (interface == nullptr) {
     log(log_level::ERROR, "Failed to get interface " + std::to_string(ifindex));
-    send_response(-1);
+    if (send_response(-1) < 0) {
+      log(log_level::ERROR, "Failed to send response for if_del_flow");
+    }
     return;
   }
   unsigned int flow_id = ntohl(if_msg->flow_id);
   int ret = interface->del_flow(flow_id);
   if (ret == 0) if_flow_ids[ifindex].erase(flow_id);
-  send_response(ret);
+  if (send_response(ret) < 0) {
+    log(log_level::ERROR, "Failed to send response for if_del_flow");
+  }
 }
 
 #endif
\ No newline at end of file