diff --git a/lib_dec/fd_cng_dec_fx.c b/lib_dec/fd_cng_dec_fx.c
index 4a13837b151bce5b3e77ce71572c0beae06e53ca..df0da51374392777a1a74645351a7d1cd88a824b 100644
--- a/lib_dec/fd_cng_dec_fx.c
+++ b/lib_dec/fd_cng_dec_fx.c
@@ -4479,7 +4479,7 @@ void generate_comfort_noise_dec_hf_ivas_fx(
         move16();
     }
 
-    randGaussExp = CNG_RAND_GAUSS_SHIFT;
+    randGaussExp = add( CNG_RAND_GAUSS_SHIFT, 1 );
     move16();
 
     /*
@@ -4503,16 +4503,16 @@ void generate_comfort_noise_dec_hf_ivas_fx(
 
                 IF( cng_coh_flag )
                 {
-                    tmp1 = rand_gauss( seed );
-                    tmp2 = rand_gauss( seed2 );
+                    rand_gauss_fx( &tmp1, seed, Q28 );
+                    rand_gauss_fx( &tmp2, seed2, Q28 );
 
                     bufferReal[i][j] = L_add( Mpy_32_16_1( tmp1, c1 ), Mpy_32_16_1( tmp2, c2 ) );
                     move32();
                     bufferReal[i][j] = L_shl( Mpy_32_32( bufferReal[i][j], sqrtNoiseLevel ), s );
                     move32();
 
-                    tmp1 = rand_gauss( seed );
-                    tmp2 = rand_gauss( seed2 );
+                    rand_gauss_fx( &tmp1, seed, Q28 );
+                    rand_gauss_fx( &tmp2, seed2, Q28 );
 
                     bufferImag[i][j] = L_add( Mpy_32_16_1( tmp1, c1 ), Mpy_32_16_1( tmp2, c2 ) );
                     move32();
@@ -4522,11 +4522,11 @@ void generate_comfort_noise_dec_hf_ivas_fx(
                 ELSE
                 {
                     /* Real part in CLDFB band */
-                    bufferReal[i][j] = L_shl( Mpy_32_32( rand_gauss( seed ), sqrtNoiseLevel ), s );
+                    bufferReal[i][j] = L_shl( Mpy_32_32( L_shr( rand_gauss( seed ), 1 ), sqrtNoiseLevel ), s );
                     move32();
 
                     /* Imaginary part in CLDFB band */
-                    bufferImag[i][j] = L_shl( Mpy_32_32( rand_gauss( seed ), sqrtNoiseLevel ), s );
+                    bufferImag[i][j] = L_shl( Mpy_32_32( L_shr( rand_gauss( seed ), 1 ), sqrtNoiseLevel ), s );
                     move32();
                 }
             }
diff --git a/lib_dec/ivas_ism_param_dec.c b/lib_dec/ivas_ism_param_dec.c
index 3f1cfbd1fffb171c46f7b880c415b0378330d5b0..e6d2085b38304f49c8e7ba058df22cebdda49b08 100644
--- a/lib_dec/ivas_ism_param_dec.c
+++ b/lib_dec/ivas_ism_param_dec.c
@@ -2591,11 +2591,20 @@ void ivas_ism_param_dec_tc_gain_ajust_fx(
     }
     ELSE
     {
-        /*handling denominator equals to zero*/
-        gain_fx = 1;
-        move16();
-        tmp_e1 = -32767;
-        move16();
+        IF( ene_tc_fx == 0 ) /*handling numerator equals to zero*/
+        {
+            gain_fx = 0;
+            move16();
+            tmp_e1 = 31;
+            move16();
+        }
+        ELSE
+        { /*handling denominator equals to zero*/
+            gain_fx = 1;
+            move16();
+            tmp_e1 = -32767;
+            move16();
+        }
     }
     tmp_e1 = add( tmp_e1, sub( ene_tc_e, ene_sum_e ) ); /* tmp_e1 + (ene_tc_e - ene_sum_e)*/
     gain_fx = Sqrt16( gain_fx, &tmp_e1 );