diff --git a/core-writer/src/module/UdpRecvModule.cpp b/core-writer/src/module/UdpRecvModule.cpp
index 1f2769f..abe2e54 100644
--- a/core-writer/src/module/UdpRecvModule.cpp
+++ b/core-writer/src/module/UdpRecvModule.cpp
@@ -81,9 +81,13 @@ void UdpRecvModule::receive_thread(
         UdpReceiver udp_receiver;
         udp_receiver.bind(udp_port);
 
+        auto metadata = make_shared<UdpFrameMetadata>();
+        metadata->frame_bytes_size = JUNGFRAU_DATA_BYTES_PER_FRAME;
+        metadata->pulse_id = 0;
+
+        char* frame_buffer = ring_buffer_.reserve(metadata);
+
         jungfrau_packet packet_buffer;
-        char* frame_buffer = nullptr;
-        shared_ptr<UdpFrameMetadata> metadata = nullptr;
 
         while (is_receiving_.load(memory_order_relaxed)) {
 
@@ -93,27 +97,34 @@ void UdpRecvModule::receive_thread(
                 continue;
             }
 
-            auto* current_metadata = metadata.get();
+            auto* frame_metadata = metadata.get();
 
-            if (current_metadata == nullptr ||
-                packet_buffer.framenum != current_metadata->frame_index) {
+            // TODO: Horrible. Breake it down into methods.
 
-                if (frame_buffer != nullptr) {
-                    ring_buffer_.commit(metadata);
-                }
+            // First packet for this frame.
+            if (frame_metadata->pulse_id == 0) {
+                frame_metadata->frame_index = packet_buffer.framenum;
+                frame_metadata->pulse_id = packet_buffer.bunchid;
+                frame_metadata->recv_packets_1 = ~(uint64_t)0;
+                frame_metadata->recv_packets_2 = ~(uint64_t)0;
+                frame_metadata->daq_rec = packet_buffer.debug;
+            // Packet from new frame, while we lost the last packet of
+            // previous frame.
+            } else if (frame_metadata->pulse_id != packet_buffer.bunchid) {
+                ring_buffer_.commit(metadata);
 
                 metadata = make_shared<UdpFrameMetadata>();
-                current_metadata = metadata.get();
-
-                current_metadata->frame_index = packet_buffer.framenum;
-                current_metadata->pulse_id = packet_buffer.bunchid;
-                current_metadata->frame_bytes_size = JUNGFRAU_DATA_BYTES_PER_FRAME;
-                current_metadata->recv_packets_1 = ~(uint64_t)0;
-                current_metadata->recv_packets_2 = ~(uint64_t)0;
-                current_metadata->daq_rec = packet_buffer.debug;
+                metadata->frame_bytes_size = JUNGFRAU_DATA_BYTES_PER_FRAME;
+                metadata->pulse_id = 0;
 
                 frame_buffer = ring_buffer_.reserve(metadata);
                 memset(frame_buffer, 0, JUNGFRAU_DATA_BYTES_PER_FRAME);
+
+                frame_metadata->frame_index = packet_buffer.framenum;
+                frame_metadata->pulse_id = packet_buffer.bunchid;
+                frame_metadata->recv_packets_1 = ~(uint64_t)0;
+                frame_metadata->recv_packets_2 = ~(uint64_t)0;
+                frame_metadata->daq_rec = packet_buffer.debug;
             }
 
             size_t frame_buffer_offset =
@@ -125,12 +136,25 @@ void UdpRecvModule::receive_thread(
                     JUNGFRAU_DATA_BYTES_PER_PACKET);
 
             if (packet_buffer.packetnum < 64) {
-                current_metadata->recv_packets_1 ^=
+                frame_metadata->recv_packets_1 ^=
                         (uint64_t)1 << packet_buffer.packetnum;
             } else {
-                current_metadata->recv_packets_2 ^=
+                frame_metadata->recv_packets_2 ^=
                         (uint64_t)1 << (packet_buffer.packetnum - 64);
             }
+
+            // Frame finished with last packet.
+            if (packet_buffer.packetnum == JUNGFRAU_N_PACKETS_PER_FRAME-1)
+            {
+                ring_buffer_.commit(metadata);
+
+                metadata = make_shared<UdpFrameMetadata>();
+                metadata->frame_bytes_size = JUNGFRAU_DATA_BYTES_PER_FRAME;
+                metadata->pulse_id = 0;
+
+                frame_buffer = ring_buffer_.reserve(metadata);
+                memset(frame_buffer, 0, JUNGFRAU_DATA_BYTES_PER_FRAME);
+            }
         }
 
     } catch (const std::exception& e) {