diff --git a/srtcore/buffer_rcv.cpp b/srtcore/buffer_rcv.cpp
index 1f46788aa..7ea0945bc 100644
--- a/srtcore/buffer_rcv.cpp
+++ b/srtcore/buffer_rcv.cpp
@@ -130,7 +130,7 @@ CRcvBuffer::CRcvBuffer(int initSeqNo, size_t size, CUnitQueue* unitqueue, bool b
     , m_bMessageAPI(bMessageAPI)
     , m_iBytesCount(0)
     , m_iPktsCount(0)
-    , m_uAvgPayloadSz(SRT_LIVE_DEF_PLSIZE)
+    , m_uAvgPayloadSz(0)
 {
     SRT_ASSERT(size < size_t(std::numeric_limits<int>::max())); // All position pointers are integers
 }
@@ -758,7 +758,12 @@ void CRcvBuffer::countBytes(int pkts, int bytes)
     m_iBytesCount += bytes; // added or removed bytes from rcv buffer
     m_iPktsCount  += pkts;
     if (bytes > 0)          // Assuming one pkt when adding bytes
-        m_uAvgPayloadSz = avg_iir<100>(m_uAvgPayloadSz, (unsigned) bytes);
+    {
+        if (!m_uAvgPayloadSz)
+            m_uAvgPayloadSz = bytes;
+        else
+            m_uAvgPayloadSz = avg_iir<100>(m_uAvgPayloadSz, (unsigned) bytes);
+    }
 }
 
 void CRcvBuffer::releaseUnitInPos(int pos)
diff --git a/srtcore/channel.cpp b/srtcore/channel.cpp
index 091adf115..38ce5b598 100644
--- a/srtcore/channel.cpp
+++ b/srtcore/channel.cpp
@@ -1016,6 +1016,15 @@ srt::EReadStatus srt::CChannel::recvfrom(sockaddr_any& w_addr, CPacket& w_packet
             if ((msg_flags & errmsgflg[i].first) != 0)
                 flg << " " << errmsgflg[i].second;
 
+        if (msg_flags & MSG_TRUNC)
+        {
+            // Additionally show buffer information in this case
+            flg << " buffers: ";
+            for (size_t i = 0; i < CPacket::PV_SIZE; ++i)
+            {
+                flg << "[" << w_packet.m_PacketVector[i].iov_len << "] ";
+            }
+        }
         // This doesn't work the same way on Windows, so on Windows just skip it.
 #endif
 
diff --git a/srtcore/common.cpp b/srtcore/common.cpp
index b621c8025..dc60b3db7 100644
--- a/srtcore/common.cpp
+++ b/srtcore/common.cpp
@@ -205,7 +205,7 @@ void srt::CIPAddress::pton(sockaddr_any& w_addr, const uint32_t ip[4], const soc
     {
         // Check if the peer address is a model of IPv4-mapped-on-IPv6.
         // If so, it means that the `ip` array should be interpreted as IPv4.
-        const bool is_mapped_ipv4 = checkMappedIPv4((uint16_t*)peer.sin6.sin6_addr.s6_addr);
+        const bool is_mapped_ipv4 = checkMappedIPv4(peer.sin6);
 
         sockaddr_in6* a = (&w_addr.sin6);
 
diff --git a/srtcore/common.h b/srtcore/common.h
index 5021fa5a8..de42a7d83 100644
--- a/srtcore/common.h
+++ b/srtcore/common.h
@@ -1422,6 +1422,15 @@ inline std::string SrtVersionString(int version)
 
 bool SrtParseConfig(const std::string& s, SrtConfig& w_config);
 
+bool checkMappedIPv4(const uint16_t* sa);
+
+inline bool checkMappedIPv4(const sockaddr_in6& sa)
+{
+    const uint16_t* addr = reinterpret_cast<const uint16_t*>(&sa.sin6_addr.s6_addr);
+    return checkMappedIPv4(addr);
+}
+
+
 } // namespace srt
 
 #endif
diff --git a/srtcore/congctl.cpp b/srtcore/congctl.cpp
index 91c73d660..b9265c046 100644
--- a/srtcore/congctl.cpp
+++ b/srtcore/congctl.cpp
@@ -63,6 +63,7 @@ class LiveCC: public SrtCongestionControlBase
     int64_t  m_llSndMaxBW;          //Max bandwidth (bytes/sec)
     srt::sync::atomic<size_t>   m_zSndAvgPayloadSize;  //Average Payload Size of packets to xmit
     size_t   m_zMaxPayloadSize;
+    size_t   m_zHeaderSize;
 
     // NAKREPORT stuff.
     int m_iMinNakInterval_us;                       // Minimum NAK Report Period (usec)
@@ -81,6 +82,8 @@ class LiveCC: public SrtCongestionControlBase
             m_zMaxPayloadSize = parent->maxPayloadSize();
         m_zSndAvgPayloadSize = m_zMaxPayloadSize;
 
+        m_zHeaderSize = parent->m_config.iMSS - parent->maxPayloadSize();
+
         m_iMinNakInterval_us = 20000;   //Minimum NAK Report Period (usec)
         m_iNakReportAccel = 2;       //Default NAK Report Period (RTT) accelerator (send periodic NAK every RTT/2)
 
@@ -173,7 +176,7 @@ class LiveCC: public SrtCongestionControlBase
     void updatePktSndPeriod()
     {
         // packet = payload + header
-        const double pktsize = (double) m_zSndAvgPayloadSize.load() + CPacket::SRT_DATA_HDR_SIZE;
+        const double pktsize = (double) m_zSndAvgPayloadSize.load() + m_zHeaderSize;
         m_dPktSndPeriod = 1000 * 1000.0 * (pktsize / m_llSndMaxBW);
         HLOGC(cclog.Debug, log << "LiveCC: sending period updated: " << m_dPktSndPeriod
                 << " by avg pktsize=" << m_zSndAvgPayloadSize