diff --git a/lib_com/options.h b/lib_com/options.h
index 4d90bd9f27989137e35f2707905baa06a2b13de3..5aa3ec18d8999a901e5cf0e81920c308361dd033 100755
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -176,6 +176,7 @@
 #define NONBE_FIX_949_MC_5MS_FRAMING                          /* Dlb: issue 949: fix for issue 949, distorted output in MC mode with 5ms framing*/
 #define NONBE_FIX_952_MC_PARAMUPMIX_5MS                       /* Dlb : issue 952 : Differences between 5ms and 20ms rendering for ParamUpmix*/
 #define NONBE_FIX_968_ISM_BRIR_WITH_HEADROTATION_5MS_FIX      /* FhG : issue #968: differences between 5ms and 20ms rendering for discrete ISM with BRIR and head rotation*/
+#define NONBE_FIX_977_OSBA_GAIN_MISMATCH                      /* Dlb : issue 977 : Output gain mismatch for different bit rates in OSBA */
 
 /* ##################### End NON-BE switches ########################### */
 
diff --git a/lib_enc/ivas_osba_enc.c b/lib_enc/ivas_osba_enc.c
index 675b89c6d67a42ac884755923b26923232b9987f..bcff38b21db11cc68cb1927dab2389d7455dfe2d 100644
--- a/lib_enc/ivas_osba_enc.c
+++ b/lib_enc/ivas_osba_enc.c
@@ -72,7 +72,11 @@ static void ivas_merge_sba_transports(
     {
         for ( j = 0; j < input_frame; j++ )
         {
+#ifdef NONBE_FIX_977_OSBA_GAIN_MISMATCH
+            data_out_f[i][j] = 0.5f * ( data_in_f1[i][j] + data_in_f2[i][j] );
+#else
             data_out_f[i][j] = ( data_in_f1[i][j] + data_in_f2[i][j] );
+#endif
         }
     }
 
@@ -443,7 +447,9 @@ static void ivas_osba_render_ism_to_sba(
     int16_t azimuth, elevation;
     float gains[MAX_INPUT_CHANNELS];
     float g1, g2;
+#ifndef NONBE_FIX_977_OSBA_GAIN_MISMATCH
     float output_gain;
+#endif
 
     int16_t nchan_sba;
 
@@ -478,6 +484,7 @@ static void ivas_osba_render_ism_to_sba(
     }
 
     /* Gain with loudness-matching gains */
+#ifndef NONBE_FIX_977_OSBA_GAIN_MISMATCH
     output_gain = 0.7499f;
     for ( j = 0; j < nchan_sba; j++ )
     {
@@ -486,6 +493,7 @@ static void ivas_osba_render_ism_to_sba(
             data_out_f[j][k] *= output_gain;
         }
     }
+#endif
 
     return;
 }