diff --git a/lib_com/options.h b/lib_com/options.h
index 41ed34b2f72e42485a91a9d555fcfe7e2ff002b0..8a3a5e7b38f50669b1c6d1f627a0d9078011373e 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -166,7 +166,6 @@
 #define FIX_822_REFACTOR_BIN_REVERB_OPEN                /* Nokia: Addresses first step of issue 822 by refactoring ivas_binaural_reverb_open */
 #define FIX_847_OUTPUT_PCM_BUFFER                       /* VA: issue 847: Allocate decoder output PCM buffer dynamically */
 
-
 /* #################### End BE switches ################################## */
 
 
@@ -188,6 +187,7 @@
 #define NONBE_FIX_838_CRASH_24_4_WB                           /* FhG: Issue 838: fix encoder crashes for Unified Stereo and MASA 2 TC at 24.4 kbps WB due to missing IGF (re-) allocation */
 #define NONBE_FIX_839_MC_RS_CHANNEL_ALLOC                     /* FhG: Issues #839: problems with reallocation of the channels on the heap in case of MC RS */
 #define BE_FIX_832_ASAN_ERROR_EFAP_OSBA                       /* FhG: issue #832: fix ASAN error caused by re-allocating EFAP memories in OSBA*/
+#define NONBE_FIX_819_DOUBLE_PREC_COMB_FORMATS                /* VA: issue 820: Double precision arithmetic in combined formats */
 
 
 /* ##################### End NON-BE switches ########################### */
diff --git a/lib_enc/ivas_omasa_enc.c b/lib_enc/ivas_omasa_enc.c
index 304f45c7ebf14e56748781942b5c99c919f1d8e3..7a17117acd0d8a1c0aafb5efa6b00a7ebe4ee588 100644
--- a/lib_enc/ivas_omasa_enc.c
+++ b/lib_enc/ivas_omasa_enc.c
@@ -127,7 +127,11 @@ ivas_error ivas_omasa_enc_open(
 
     for ( i = 0; i < MAX_NUM_OBJECTS; i++ )
     {
+#ifdef NONBE_FIX_819_DOUBLE_PREC_COMB_FORMATS
+        set_f( hOMasa->prev_object_dm_gains[i], INV_SQRT_2, MASA_MAX_TRANSPORT_CHANNELS );
+#else
         set_f( hOMasa->prev_object_dm_gains[i], (float) sqrt( 0.5 ), MASA_MAX_TRANSPORT_CHANNELS );
+#endif
     }
     set_zero( hOMasa->broadband_energy_sm, MAX_NUM_OBJECTS + MASA_MAX_TRANSPORT_CHANNELS );
     set_zero( hOMasa->broadband_energy_prev, MAX_NUM_OBJECTS + MASA_MAX_TRANSPORT_CHANNELS );
diff --git a/lib_enc/ivas_osba_enc.c b/lib_enc/ivas_osba_enc.c
index 788796d4a0de4d695abb3e171f104e6afa69cb22..7c4e844f4528a64ab7ad5cb32bd2b7605b0b06f9 100644
--- a/lib_enc/ivas_osba_enc.c
+++ b/lib_enc/ivas_osba_enc.c
@@ -102,10 +102,13 @@ ivas_error ivas_osba_enc_open(
         return ( IVAS_ERROR( IVAS_ERR_FAILED_ALLOC, "Can not allocate memory for OMASA encoder\n" ) );
     }
 
-
     for ( i = 0; i < MAX_NUM_OBJECTS; i++ )
     {
+#ifdef NONBE_FIX_819_DOUBLE_PREC_COMB_FORMATS
+        set_f( hOSba->prev_object_dm_gains[i], INV_SQRT_2, MAX_INPUT_CHANNELS );
+#else
         set_f( hOSba->prev_object_dm_gains[i], (float) sqrt( 0.5 ), MAX_INPUT_CHANNELS );
+#endif
     }
 
     len = NS2SA( st_ivas->hEncoderConfig->input_Fs, IVAS_FB_ENC_DELAY_NS );
diff --git a/lib_rend/ivas_omasa_ana.c b/lib_rend/ivas_omasa_ana.c
index 7284acb8cfc2761943cc9d64abd89830764e7696..3114e8dd24262cab32a39b8d96f677cbc8b0b8f3 100644
--- a/lib_rend/ivas_omasa_ana.c
+++ b/lib_rend/ivas_omasa_ana.c
@@ -150,7 +150,11 @@ ivas_error ivas_omasa_ana_open(
 
     for ( i = 0; i < MAX_NUM_OBJECTS; i++ )
     {
+#ifdef NONBE_FIX_819_DOUBLE_PREC_COMB_FORMATS
+        set_f( hOMasa->prev_object_dm_gains[i], INV_SQRT_2, MASA_MAX_TRANSPORT_CHANNELS );
+#else
         set_f( hOMasa->prev_object_dm_gains[i], (float) sqrt( 0.5 ), MASA_MAX_TRANSPORT_CHANNELS );
+#endif
     }
 
     input_frame = (int16_t) ( input_Fs / FRAMES_PER_SEC );