diff --git a/lib_com/options.h b/lib_com/options.h
index 0ea316a82a8cdacb4562394ba7ad6b5cd236a9bd..400b3fa163825c786f9660d96f6df97b3a0ef4f2 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -109,7 +109,7 @@
 #define FIX_2391_INIT_HQ_GENERIC_OFFSET                 /* FhG/Eri: basop issue 2391: make sure hq_generic_offset is initialized inside hq_hr_dec_fx() */
 #define FIX_2397_COPY_AQ_MDCT_CORE_BFI                  /* FhG: prevent copying of uninit memory in MDCT stereo core if bfi is set */
 #define HARMONIZE_TBE                                   /* VA: harmonize core-coder TBE function duplications */
-
+#define HARMONIZE_READ_DECODE_TNS                       /* FhG: issue 2389: Harmonization of two pairs ReadTnsData() and DecodeTnsData()*/
 /* #################### End BE switches ################################## */
 
 /* #################### Start NON-BE switches ############################ */
diff --git a/lib_com/parameter_bitmaping_fx.c b/lib_com/parameter_bitmaping_fx.c
index 4225879e6b20e56584e35c4bc40240cfc0112337..5a2f8ccfe640147dd4798ff6246940ac0a119ee9 100644
--- a/lib_com/parameter_bitmaping_fx.c
+++ b/lib_com/parameter_bitmaping_fx.c
@@ -228,8 +228,15 @@ void SetParameters_fx(
             IF( s_and( param->pSubParamBitMap != NULL, value > 0 ) )
             {
                 pTmp = pParameter;
+#ifdef HARMONIZE_READ_DECODE_TNS
                 if ( pSubStruct != NULL )
+                {
                     pTmp = pSubStruct;
+                }
+#else
+                if ( pSubStruct != NULL )
+                    pTmp = pSubStruct;
+#endif
                 SetParameters( param->pSubParamBitMap, value, pTmp, pStream, pnSize );
             }
         }
diff --git a/lib_com/prot_fx.h b/lib_com/prot_fx.h
index c45c2a7490d98886919391ee55e3dcb80560eff0..baa38d4cfbd16420a5f5f8d5e615f528e590c646 100644
--- a/lib_com/prot_fx.h
+++ b/lib_com/prot_fx.h
@@ -8375,7 +8375,21 @@ void tcx_hm_modify_envelope(
     Word32 env[],     /* i/o: envelope                          Q16 */
     Word16 L_frame    /* i:   number of spectral lines          Q0  */
 );
+#ifdef HARMONIZE_READ_DECODE_TNS
+Word16 ReadTnsData(
+    STnsConfig const *pTnsConfig,
+    Decoder_State *st,
+    Word16 *pnBits,
+    Word16 *stream,
+    Word16 *pnSize );
 
+Word16 DecodeTnsData(
+    STnsConfig const *pTnsConfig,
+    Word16 const *stream, /*Q0*/
+    Word16 *pnSize,       /*Q0*/
+    STnsData *pTnsData );
+
+#else
 Word16 ReadTnsData(
     STnsConfig const *pTnsConfig,
     Decoder_State *st,
@@ -8402,6 +8416,7 @@ Word16 DecodeTnsData_ivas_fx(
     Word16 *pnSize,
     STnsData *pTnsData );
 
+#endif
 void GetParameters(
     ParamsBitMap const *paramsBitMap,
     const Word16 nParams,
@@ -11062,12 +11077,6 @@ void EncodeTnsData(
     Word16 *pnBits                /* o  : number of written bits            */
 );
 
-Word16 DecodeTnsData_ivas(
-    STnsConfig const *pTnsConfig,
-    const Word16 *stream,
-    Word16 *pnSize,
-    STnsData *pTnsData );
-
 void WriteTnsData(
     const STnsConfig *pTnsConfig, /* i  : TNS Configuration struct          */
     const Word16 *stream,         /* i  : internal data stream              */
@@ -11075,7 +11084,7 @@ void WriteTnsData(
     BSTR_ENC_HANDLE hBstr,        /* o  : bitstream                         */
     Word16 *pnBits                /* o  : number of written bits            */
 );
-
+#ifndef HARMONIZE_READ_DECODE_TNS
 void ReadTnsData_ivas(
     STnsConfig const *pTnsConfig,
     Decoder_State *st,
@@ -11083,6 +11092,13 @@ void ReadTnsData_ivas(
     Word16 *stream,
     Word16 *pnSize );
 
+Word16 DecodeTnsData_ivas(
+    STnsConfig const *pTnsConfig,
+    const Word16 *stream,
+    Word16 *pnSize,
+    STnsData *pTnsData );
+
+#endif // HARMONIZE_READ_DECODE_TNS
 void analysisCldfbEncoder_ivas_fx(
     Encoder_State *st,       /* i/o: encoder state structure   */
     Word32 *timeIn,          /*q11*/
diff --git a/lib_dec/dec_prm_fx.c b/lib_dec/dec_prm_fx.c
index 41a2e9842cd2657b9f28f019e4a75462e9e93f22..853ac4222d1341c75ab7f0dd63e172224fbce32e 100644
--- a/lib_dec/dec_prm_fx.c
+++ b/lib_dec/dec_prm_fx.c
@@ -394,7 +394,13 @@ void getTCXparam_fx(
                 }
                 ELSE
                 {
+#ifdef HARMONIZE_READ_DECODE_TNS
+
+                    (void) ReadTnsData( st->hTcxCfg->pCurrentTnsConfig, st0, &nTnsBits, prm + j, &nTnsParams );
+#else
+
                     ReadTnsData_ivas_fx( st->hTcxCfg->pCurrentTnsConfig, st0, &nTnsBits, prm + j, &nTnsParams );
+#endif // HARMONIZE_READ_DECODE_TNS
                 }
                 hTcxDec->tnsActive[k] = 0; // Q0
                 move16();
@@ -1351,7 +1357,11 @@ void dec_prm_fx(
         IF( st->hTcxCfg->fIsTNSAllowed )
         {
             SetTnsConfig( st->hTcxCfg, 1, (Word16) EQ_16( st->last_core_from_bs, ACELP_CORE ) );
+#ifdef HARMONIZE_READ_DECODE_TNS
+            (void) ReadTnsData( st->hTcxCfg->pCurrentTnsConfig, st, &nTnsBits, prm + j, &nTnsParams );
+#else
             ReadTnsData( st->hTcxCfg->pCurrentTnsConfig, st, &nTnsBits, prm + j, &nTnsParams );
+#endif //  HARMONIZE_READ_DECODE_TNS
 
             j = add( j, nTnsParams ); // Q0
         }
@@ -1675,8 +1685,13 @@ void dec_prm_fx(
                 test();
                 test();
                 SetTnsConfig( st->hTcxCfg, 0, ( st->last_core_from_bs == ACELP_CORE ) && ( k == 0 ) );
-
+#ifdef HARMONIZE_READ_DECODE_TNS
+                (void) ReadTnsData( st->hTcxCfg->pCurrentTnsConfig, st, &nTnsBits, prm + j, &nTnsParams );
+#else
                 ReadTnsData( st->hTcxCfg->pCurrentTnsConfig, st, &nTnsBits, prm + j, &nTnsParams );
+#endif // DEBUG
+
+
                 j = add( j, nTnsParams );
             }
 
diff --git a/lib_dec/dec_tcx_fx.c b/lib_dec/dec_tcx_fx.c
index ed170d5982cf679da5651bb1eb9ef3adc4683609..534d342756de37f149fb028bb0d39dea02c06dee 100644
--- a/lib_dec/dec_tcx_fx.c
+++ b/lib_dec/dec_tcx_fx.c
@@ -4204,7 +4204,7 @@ void decoder_tcx_invQ_fx(
     test();
     IF( !bfi && hTcxCfg->fIsTNSAllowed )
     {
-        *fUseTns = DecodeTnsData_ivas_fx( hTcxCfg->pCurrentTnsConfig, prm_tns, &tnsSize, tnsData );
+        *fUseTns = DecodeTnsData( hTcxCfg->pCurrentTnsConfig, prm_tns, &tnsSize, tnsData );
         move16();
     }
     ELSE
diff --git a/lib_dec/tns_base_dec_fx.c b/lib_dec/tns_base_dec_fx.c
index e245a4674acca3a9eed93f2b189caec8036ade81..42fd51df7e0bc986f8a141f0668a41c5d28a544e 100644
--- a/lib_dec/tns_base_dec_fx.c
+++ b/lib_dec/tns_base_dec_fx.c
@@ -21,6 +21,120 @@ typedef Word32 ( *TLinearPredictionFilter )( Word16 order, Word16 const parCoeff
 /********************************/
 /*      Interface functions     */
 /********************************/
+
+
+#ifdef HARMONIZE_READ_DECODE_TNS
+/*---------------------------------------------------------------------*
+ * ReadTnsData()
+ *
+ *
+ *---------------------------------------------------------------------*/
+Word16 ReadTnsData(
+    STnsConfig const *pTnsConfig,
+    Decoder_State *st,
+    Word16 *pnBits, /*Q0*/
+    Word16 *stream, /*Q0*/
+    Word16 *pnSize  /*Q0*/
+)
+{
+    Word16 start_bit_pos;
+
+    move16();
+    start_bit_pos = st->next_bit_pos;
+
+    IF( GT_16( pTnsConfig->nMaxFilters, 1 ) )
+    {
+        IF( pTnsConfig->allowTnsOnWhite )
+        {
+            IF( LT_16( pTnsConfig->iFilterBorders[0], 512 ) )
+            {
+                ReadFromBitstream_fx( &tnsEnabledOnWhiteSWBTCX10BitMap, 1, st, &stream, pnSize );
+            }
+            ELSE
+            {
+                ReadFromBitstream_fx( &tnsEnabledOnWhiteSWBTCX20BitMap, 1, st, &stream, pnSize );
+            }
+        }
+        ELSE
+        {
+
+            IF( LT_16( pTnsConfig->iFilterBorders[0], 512 ) )
+            {
+                ReadFromBitstream_fx( &tnsEnabledSWBTCX10BitMap, 1, st, &stream, pnSize );
+            }
+            ELSE
+            {
+                ReadFromBitstream_fx( &tnsEnabledSWBTCX20BitMap, 1, st, &stream, pnSize );
+            }
+        }
+    }
+    ELSE
+    {
+        ReadFromBitstream_fx( &tnsEnabledWBTCX20BitMap, 1, st, &stream, pnSize );
+    }
+
+    move16();
+    *pnBits = sub( st->next_bit_pos, start_bit_pos );
+
+    return TNS_NO_ERROR;
+}
+/*---------------------------------------------------------------------*
+ * DecodeTnsData()
+ *
+ *
+ *---------------------------------------------------------------------*/
+Word16 DecodeTnsData(
+    STnsConfig const *pTnsConfig,
+    Word16 const *stream, /*Q0*/
+    Word16 *pnSize,       /*Q0*/
+    STnsData *pTnsData )
+{
+    Word16 result;
+
+    ResetTnsData( pTnsData );
+
+    IF( GT_16( pTnsConfig->nMaxFilters, 1 ) )
+    {
+
+        IF( pTnsConfig->allowTnsOnWhite )
+        {
+            IF( LT_16( pTnsConfig->iFilterBorders[0], 512 ) )
+            {
+                SetParameters_fx( &tnsEnabledOnWhiteSWBTCX10BitMap, 1, pTnsData, &stream, pnSize );
+            }
+            ELSE
+            {
+                SetParameters_fx( &tnsEnabledOnWhiteSWBTCX20BitMap, 1, pTnsData, &stream, pnSize );
+            }
+        }
+        ELSE
+        {
+
+            IF( LT_16( pTnsConfig->iFilterBorders[0], 512 ) )
+            {
+                SetParameters_fx( &tnsEnabledSWBTCX10BitMap, 1, pTnsData, &stream, pnSize );
+            }
+            ELSE
+            {
+                SetParameters_fx( &tnsEnabledSWBTCX20BitMap, 1, pTnsData, &stream, pnSize );
+            }
+        }
+    }
+    ELSE
+    {
+        SetParameters_fx( &tnsEnabledWBTCX20BitMap, 1, pTnsData, &stream, pnSize );
+    }
+
+    move16();
+    result = FALSE;
+    if ( pTnsData->nFilters > 0 )
+    {
+        move16();
+        result = TRUE;
+    }
+    return result;
+}
+#else
 /*---------------------------------------------------------------------*
  * ReadTnsData()
  *
@@ -216,3 +330,6 @@ Word16 DecodeTnsData_ivas_fx(
 
     return result;
 }
+
+
+#endif // HARMONIZE_READ_DECODE_TNS