diff --git a/changelog.txt b/changelog.txt
index 7913832..5a21d18 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -60,6 +60,8 @@ chg: with r_backend GL3, depth fade with MSAA now requires GLSL 4.00 at a minimu
 
 chg: with r_backend GL3, alpha to coverage now requires GLSL 4.00 at a minimum
 
+fix: /video was writing incorrect audio stream lengths to the .avi file headers
+
 fix: /systeminfo /serverinfo /clientinfo /dumpuser would crash when tokens were too long
 
 fix: with r_lightmap 1 and r_dynamiclight 1, lighting transparent surfaces could crash
diff --git a/code/client/cl_avi.cpp b/code/client/cl_avi.cpp
index 6730c52..98a7aa4 100644
--- a/code/client/cl_avi.cpp
+++ b/code/client/cl_avi.cpp
@@ -548,7 +548,7 @@ void CL_WriteAVIAudioFrame( const byte *pcmBuffer, int size )
 
     afd.numAudioFrames++;
     afd.moviSize += ( chunkSize + paddingSize );
-    afd.a.totalBytes =+ bytesInBuffer;
+    afd.a.totalBytes += bytesInBuffer;
 
     // Index
     bufIndex = 0;