diff --git a/lib_com/fd_cng_com_fx.c b/lib_com/fd_cng_com_fx.c
index 4975876357e8d2d973ec5cb7168406626378e000..9b13274d8799938f6a6f7df8da87d0eadf8629e9 100644
--- a/lib_com/fd_cng_com_fx.c
+++ b/lib_com/fd_cng_com_fx.c
@@ -112,6 +112,10 @@ void initFdCngCom(
     move16();
     hFdCngCom->stopFFTbin = 0;
     move16();
+#ifdef FIX_1559
+    hFdCngCom->nFFTpart = 0;
+    move16();
+#endif
     hFdCngCom->frameSize = 0;
     move16();
     hFdCngCom->fftlen = 0;
diff --git a/lib_com/options.h b/lib_com/options.h
index 66f09059ca958bd8b4fc18c56496f0ec814319f0..0d3c1fa93ae22bd5693c752dd96248ce04339906 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -155,6 +155,7 @@
 #define FIX_BASOP_2559_Q_SYNTH_HISTORY_RESET            /* FhG: BASOP issue 2559: reset hTcxDec->q_synth_history_fx in allocate_CoreCoder_TCX_fx() */
 #define FIX_FLOAT_1578_OMASA_REND_SPIKES                /* Nokia: Float issue 1578: Fix spikes and collapsed perception in OMASA/MASA rendering to FOA/HOA */
 #define FIX_1521_SBA_LOUDNESS_STEREO                    /* FhG: issue 1521: Fix loudness for SBA to stereo rendering */
+#define FIX_1559                                        /* Eri/FhG: fix for Issue 1559 in FD CNG with bitrate/bw switching */
 
 /* ##################### End NON-BE switches ########################### */
 
diff --git a/lib_dec/fd_cng_dec_fx.c b/lib_dec/fd_cng_dec_fx.c
index 5fced60ad842dcbd8c5b13e0d8860e319e0352dd..6f4363229c6ae7d31467862e636aed6eada94e37 100644
--- a/lib_dec/fd_cng_dec_fx.c
+++ b/lib_dec/fd_cng_dec_fx.c
@@ -4155,6 +4155,9 @@ void configureFdCngDec_ivas_fx(
 {
     Word16 j, stopBandFR;
     HANDLE_FD_CNG_COM hsCom = hFdCngDec->hFdCngCom;
+#ifdef FIX_1559
+    Word16 nFFTpart_prev;
+#endif
 
     hsCom->CngBandwidth = bwidth; /*Q0*/
     move16();
@@ -4289,6 +4292,10 @@ void configureFdCngDec_ivas_fx(
     hsCom->stopBand = add( hsCom->FdCngSetup.sidPartitions[( hsCom->FdCngSetup.numPartitions - 1 )], 1 ); /*Q0*/
     initPartitions( hsCom->FdCngSetup.sidPartitions, hsCom->FdCngSetup.numPartitions, hsCom->startBand, hsCom->stopBand, hsCom->part, &hsCom->npart, hsCom->midband, hsCom->psize, hsCom->psize_norm, &hsCom->psize_norm_exp, hsCom->psize_inv, 0 );
 
+#ifdef FIX_1559
+    nFFTpart_prev = hsCom->nFFTpart;
+    move16();
+#endif
     IF( EQ_16( hsCom->stopFFTbin, 160 ) )
     {
         hsCom->nFFTpart = 17;
@@ -4314,6 +4321,21 @@ void configureFdCngDec_ivas_fx(
         move16();
     }
 
+#ifdef FIX_1559
+    /* In case of going from a lower number of partitions to a higher number, initialize
+    the higher ines which might be zero and/or outdated with the highest partitions value
+    this avoids almost-zero values to linger around and causing signal bursts after switching to higher bitrate.
+    Don't do this on initialization of the codec (nFFTpart_prev == 0)*/
+    IF( NE_16( nFFTpart_prev, 0 ) )
+    {
+        FOR( j = nFFTpart_prev; j < hsCom->nFFTpart; ++j )
+        {
+            hFdCngDec->partNoiseShape[j] = hFdCngDec->partNoiseShape[nFFTpart_prev - 1];
+            move16();
+        }
+    }
+#endif
+
     stopBandFR = 40; //(Word16)floor(1000.f /*Hz*/ / 25.f /*Hz/Bin*/);
     move16();
     if ( GT_16( stopBandFR, hsCom->stopFFTbin ) )