diff --git a/trunk/src/kernel/srs_kernel_rtc_rtcp.cpp b/trunk/src/kernel/srs_kernel_rtc_rtcp.cpp
index b0d96a495..133d2dd8c 100644
--- a/trunk/src/kernel/srs_kernel_rtc_rtcp.cpp
+++ b/trunk/src/kernel/srs_kernel_rtc_rtcp.cpp
@@ -1346,9 +1346,11 @@ srs_error_t SrsRtcpNack::encode(SrsBuffer *buffer)
             if((sn - pid) < 1) {
                 srs_info("skip seq %d", sn);
             } else if( (sn - pid) > 16) {
-                // add new chunk
+                // append full chunk
                 chunks.push_back(chunk);
-		chunk.pid = sn;
+
+                // start new chunk
+                chunk.pid = sn;
                 chunk.blp = 0;
                 chunk.in_use = true;
                 pid = sn;
diff --git a/trunk/src/utest/srs_utest_rtc.cpp b/trunk/src/utest/srs_utest_rtc.cpp
index 4f24ab1e9..b8b61769d 100644
--- a/trunk/src/utest/srs_utest_rtc.cpp
+++ b/trunk/src/utest/srs_utest_rtc.cpp
@@ -1169,6 +1169,36 @@ VOID TEST(KernelRTCTest, SyncTimestampBySenderReportConsecutive)
     }
 }
 
+VOID TEST(KernelRTCTest, SrsRtcpNack)
+{
+    uint32_t sender_ssrc = 0x0A;
+    uint32_t media_ssrc = 0x0B;
+
+    SrsRtcpNack nack_encoder(sender_ssrc);
+    nack_encoder.set_media_ssrc(media_ssrc);
+
+    for (uint16_t seq = 15; seq < 45; seq++) {
+        nack_encoder.add_lost_sn(seq);
+    }
+    EXPECT_FALSE(nack_encoder.empty());
+
+    char buf[kRtcpPacketSize];
+    SrsBuffer stream(buf, sizeof(buf));
+
+    srs_error_t err = srs_success;
+    err = nack_encoder.encode(&stream);
+    EXPECT_EQ(srs_error_code(err), srs_success);
+
+    SrsRtcpNack nack_decoder;
+    stream.skip(-stream.pos());
+    err = nack_decoder.decode(&stream);
+    EXPECT_EQ(srs_error_code(err), srs_success);
+
+    vector<uint16_t> actual_lost_sn = nack_encoder.get_lost_sns();
+    vector<uint16_t> req_lost_sns = nack_decoder.get_lost_sns();
+    EXPECT_EQ(actual_lost_sn.size(), req_lost_sns.size());
+}
+
 VOID TEST(KernelRTCTest, SyncTimestampBySenderReportDuplicated)
 {
     SrsRtcConnection s(NULL, SrsContextId()); 
@@ -1243,3 +1273,4 @@ VOID TEST(KernelRTCTest, SyncTimestampBySenderReportDuplicated)
         }
     }
 }
+