diff --git a/lib_com/options.h b/lib_com/options.h
index 61a3c10ccfc2662a6854e6d6fc182f24dde9d839..954f24ce4e8160baed4cd2562a3c925c6cc5571c 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -87,6 +87,7 @@
 #define FIX_2388_INITTNSCONFIGURATION                   /* FhG: issue 2388 : harmonizing InitTnsConfiguration() function */
 #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 FIX_2387_ANALYZEPOWERSPECTRUM                   /* FhG: harmonize AnalyzePowerSpectrum_fx() and AnalyzePowerSpectrum_ivas_fx() */
 #define FIX_2405_HARM_SMC_INIT                          /* VA, basop 2405, harmonisation of SMC init */
 #define FIX_2280_REDUCTION_UNNECESSARY_SCALING          /* VA: reduction of unnecessary scaling */
 #define FIX_2280_REDUCTION_UNNECESSARY_SCALING_NONBE    /* VA: reduction of unnecessary scaling, non-BE part */
diff --git a/lib_enc/cod_tcx_fx.c b/lib_enc/cod_tcx_fx.c
index d2dd0bf03f841acdada0a5f3f5d395ec07fb083f..feac17912ce62d0ad5cab0a9083fb189dd4bcfb3 100644
--- a/lib_enc/cod_tcx_fx.c
+++ b/lib_enc/cod_tcx_fx.c
@@ -3833,7 +3833,18 @@ void coder_tcx_fx(
         pWinMDST = win;
         move16();
     }
-
+#ifdef FIX_2387_ANALYZEPOWERSPECTRUM
+    AnalyzePowerSpectrum_ivas_fx( st,
+                                  round_fx( L_shl( Mpy_32_16_1( L_mult0( L_frame, st->L_frame ) /*Q0*/,
+                                                                getInvFrameLen( hTcxEnc->L_frameTCX ) /*Q21*/ ) /*Q6*/,
+                                                   16 - 6 ) ),
+                                  L_frame,
+                                  left_overlap, right_overlap,
+                                  spectrum, *spectrum_e,
+                                  pWinMDST,
+                                  16 - *spectrum_e,
+                                  powerSpec, &powerSpec_e );
+#else
     AnalyzePowerSpectrum_fx( st,
                              round_fx( L_shl( Mpy_32_16_1( L_mult0( L_frame, st->L_frame ) /*Q0*/,
                                                            getInvFrameLen( hTcxEnc->L_frameTCX ) /*Q21*/ ) /*Q6*/,
@@ -3843,6 +3854,7 @@ void coder_tcx_fx(
                              spectrum, *spectrum_e,
                              pWinMDST,
                              powerSpec, &powerSpec_e );
+#endif
     IF( hTcxCfg->fIsTNSAllowed != 0 )
     {
 
diff --git a/lib_enc/ext_sig_ana_fx.c b/lib_enc/ext_sig_ana_fx.c
index 33181714765ea239bdf078dacdcc47392a934156..3a45821520d9d24cb16466277148399677475ca8 100644
--- a/lib_enc/ext_sig_ana_fx.c
+++ b/lib_enc/ext_sig_ana_fx.c
@@ -395,9 +395,15 @@ void core_signal_analysis_high_bitrate_fx(
                     }
 
                     /* Compute noise-measure flags for spectrum filling and quantization */
+#ifdef FIX_2387_ANALYZEPOWERSPECTRUM
+                    AnalyzePowerSpectrum_ivas_fx( st, div_l( L_mult( L_subframe, st->L_frame ), hTcxEnc->L_frameTCX ),
+                                                  L_subframe, left_overlap, right_overlap, spectrum[frameno], spectrum_e[frameno],
+                                                  pMdstWin, 16 - spectrum_e[frameno], powerSpec, &powerSpec_e );
+#else
                     AnalyzePowerSpectrum_fx( st, div_l( L_mult( L_subframe, st->L_frame ), hTcxEnc->L_frameTCX ),
                                              L_subframe, left_overlap, right_overlap, spectrum[frameno], spectrum_e[frameno],
                                              pMdstWin, powerSpec, &powerSpec_e );
+#endif
                 }
             }
         }
diff --git a/lib_enc/tcx_utils_enc_fx.c b/lib_enc/tcx_utils_enc_fx.c
index 9765655ba4d880bab90ca7e255273a39d60d3b79..98df09a3d2bd69a1a0d4326f9e0c74bc667c5426 100644
--- a/lib_enc/tcx_utils_enc_fx.c
+++ b/lib_enc/tcx_utils_enc_fx.c
@@ -316,6 +316,7 @@ static void detectLowpassFac( const Word32 *powerSpec, Word16 powerSpec_e, Word1
     move16();
 }
 
+#ifndef FIX_2387_ANALYZEPOWERSPECTRUM
 /*-----------------------------------------------------------*
  * Compute noise-measure flags for spectrum filling          *
  * and quantization (0: tonal, 1: noise-like).               *
@@ -426,6 +427,7 @@ void AnalyzePowerSpectrum_fx(
         move16();
     }
 }
+#endif /* FIX_2387_ANALYZEPOWERSPECTRUM */
 
 void AnalyzePowerSpectrum_ivas_fx(
     Encoder_State *st,           /* i/o: encoder states                                  */