diff --git a/lib_com/basop32.c b/lib_com/basop32.c
index 5a5a434846333bbcc752cf8e1e0dbcfa5ab08241..704b2e21b36fc338419b3cfe11093e7b6e3b3ef0 100644
--- a/lib_com/basop32.c
+++ b/lib_com/basop32.c
@@ -616,6 +616,12 @@ Word16 shl( Word16 var1, Word16 var2 )
 
     return ( var_out );
 }
+
+Word16 shl_sat( Word16 var1, Word16 var2 )
+{
+    Flag Overflow;
+    return shl_o( var1, var2, &Overflow );
+}
 #endif /* BASOP_NOGLOB */
 
 /*___________________________________________________________________________
diff --git a/lib_com/basop32.h b/lib_com/basop32.h
index a8a72aed04825925a8ce418730d929c571b70203..c72e18e82462bb95ca10ff995e823309c24599f3 100644
--- a/lib_com/basop32.h
+++ b/lib_com/basop32.h
@@ -252,6 +252,7 @@ Word32 L_msu0( Word32 L_v3, Word16 v1, Word16 v2 ); /* 32-bit Msu w/o shift  1 *
 Word16 add_o( Word16 var1, Word16 var2, Flag *Overflow );
 Word16 sub_o( Word16 var1, Word16 var2, Flag *Overflow );
 Word16 shl_o( Word16 var1, Word16 var2, Flag *Overflow );
+Word16 shl_sat( Word16 var1, Word16 var2 );
 Word16 mult_o( Word16 var1, Word16 var2, Flag *Overflow );
 Word32 L_mult_o( Word16 var1, Word16 var2, Flag *Overflow );
 Word16 round_fx_o( Word32 L_var1, Flag *Overflow );
diff --git a/lib_com/basop_util.c b/lib_com/basop_util.c
index 197fe884082c1c57d3a8b56b9da51875bc1002a9..0b4784ef3726edc068a4c3ebfe1beca83141a214 100644
--- a/lib_com/basop_util.c
+++ b/lib_com/basop_util.c
@@ -636,6 +636,53 @@ static Word16 fixp_sin_cos_residual_16(
     return residual;
 }
 
+Word16 getCosWord16( Word16 theta )
+{
+    Word16 result, residual, sine, cosine;
+
+    residual = fixp_sin_cos_residual_16( theta, 2, &sine, &cosine, 0 );
+    /* This negation prevents the subsequent addition from overflow */
+    /* The negation cannot overflow, sine is in range [0x0..0x7FFF] */
+    sine = negate( sine );
+    result = mac_r( L_mult0( sine, residual ), cosine, 16384 );
+
+
+    return result;
+}
+
+#define EVS_PI_BY_2_FX ( Word16 )( 0x3244 ) // Q13
+#define EVS_PI_FX      25736                /* pi in Q13 */
+#define ONE_IN_Q14     16384
+
+Word16 getSinWord16( Word16 theta )
+{
+    Word16 sine;
+    Word32 theta_new = L_sub( EVS_PI_BY_2_FX, theta );
+    Word16 l_theta;
+    IF( GT_32( theta_new, EVS_PI_FX ) )
+    {
+        l_theta = extract_l( L_sub( L_sub( theta_new, EVS_PI_FX ), EVS_PI_FX ) );
+    }
+    ELSE IF( LT_32( theta_new, -EVS_PI_FX ) )
+    {
+        l_theta = extract_l( L_add( L_add( theta_new, EVS_PI_FX ), EVS_PI_FX ) );
+    }
+    ELSE
+    {
+        l_theta = extract_l( theta_new );
+    }
+    sine = getCosWord16( l_theta );
+    IF( EQ_16( sine, ONE_IN_Q14 ) )
+    {
+        sine = MAX_16;
+    }
+    ELSE
+    {
+        sine = shl( sine, 1 );
+    }
+    return sine;
+}
+
 
 Word16 getCosWord16R2(
     Word16 theta )
diff --git a/lib_com/basop_util.h b/lib_com/basop_util.h
index b76d5982f23fec7be3bd0b8ac7680b283dd75da1..5c23b55861d7e7c96b614404f8cfd82aef813ad9 100644
--- a/lib_com/basop_util.h
+++ b/lib_com/basop_util.h
@@ -273,6 +273,9 @@ Word16 mult0( Word16 x,   /* i  : Multiplier    */
  */
 Word16 getCosWord16R2( Word16 theta );
 
+Word16 getSinWord16( Word16 theta );
+Word16 getCosWord16( Word16 theta );
+
 /****************************************************************************/
 /*!
   \brief    16/16->16 unsigned integer division
diff --git a/lib_com/options.h b/lib_com/options.h
index 4c31c1480c9763e7cd41e1ce80f6c8cb195126dd..6b90358a0ac52dfe4d81cbd9dc162dea44fa208b 100755
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -185,6 +185,7 @@
 
 #define NONBE_1412_AVOID_ROUNDING_AZ_ELEV              /* FhG:  Avoid rounding when passing azimuth and elevation to efap_determine_gains() */
 #define NONBE_MDCT_ST_DTX_FIX_SUBOPT_SPATIAL_CNG       /* FhG: Fix MDCT-Stereo comfort noise for certain noise types */
+#define NONBE_TRIG_FUNC_2_BASOP_IN_DFT_STEREO          /* FhG: Fix for non-BE between different optimization levels in dft stereo code by using BASOPs for trigonometric functions */
 
 /* ##################### End NON-BE switches ########################### */
 
diff --git a/lib_enc/ivas_stereo_dft_enc.c b/lib_enc/ivas_stereo_dft_enc.c
old mode 100755
new mode 100644
index 0ae36724d89b7ea3237ae4f4e897a6569f518e2c..1cbd8b209aa4e0272be4ff2e915c2112ad6a1303
--- a/lib_enc/ivas_stereo_dft_enc.c
+++ b/lib_enc/ivas_stereo_dft_enc.c
@@ -42,6 +42,9 @@
 #include "ivas_cnst.h"
 #include "ivas_rom_com.h"
 #include "ivas_rom_enc.h"
+#ifdef NONBE_TRIG_FUNC_2_BASOP_IN_DFT_STEREO
+#include "basop_util.h"
+#endif
 #ifdef DEBUGGING
 #include "debug.h"
 #endif
@@ -1316,12 +1319,26 @@ void stereo_dft_enc_process(
 
         if ( hStereoDft->hItd->deltaItd[k_offset] != 0 && hStereoDft->hConfig->dmx_active )
         {
+#ifdef NONBE_TRIG_FUNC_2_BASOP_IN_DFT_STEREO
+            Word16 alpha_fx, c1_fx, s1_fx;
+#endif
             /*time shift channels*/
             alpha = -2.0f * EVS_PI * hStereoDft->hItd->deltaItd[k_offset] / hStereoDft->NFFT;
             c = 1.f; /*cos(0)*/
             s = 0.f; /*sin(0)*/
+#ifdef NONBE_TRIG_FUNC_2_BASOP_IN_DFT_STEREO
+            /* Use BASOPs for calculating trigonometric functions to be independent of compiler optimization levels */
+            /* convert angle to Q13 */
+            alpha_fx = (Word16) ( alpha * 8192 );
+            c1_fx = shl_sat( getCosWord16( alpha_fx ), 1 ); // Q15
+            s1_fx = getSinWord16( alpha_fx );               // Q15
+
+            c1 = c1_fx / 32768.f;
+            s1 = s1_fx / 32768.f;
+#else
             c1 = cosf( alpha );
             s1 = sinf( alpha );
+#endif
 
             if ( alpha >= 0 )
             {