diff --git a/apps/decoder.c b/apps/decoder.c
index e362972866613be95f6be0aef0287dc36fac3628..c25a282e1fe16a60520c2cc93c16cb5eb146938b 100644
--- a/apps/decoder.c
+++ b/apps/decoder.c
@@ -176,14 +176,22 @@ typedef struct
 static bool parseCmdlIVAS_dec( int16_t argc, char **argv, DecArguments *arg );
 static void usage_dec( void );
 static ivas_error decodeG192( DecArguments arg, BS_READER_HANDLE hBsReader, IVAS_DEC_HRTF_BINARY_WRAPPER *hHrtfBinary, RotFileReader *headRotReader, RotFileReader *externalOrientationFileReader, RotFileReader *refRotReader, Vector3PairFileReader *referenceVectorReader, ObjectEditFileReader *objectEditFileReader, ISAR_SPLIT_REND_BITS_DATA *splitRendBits, IVAS_DEC_HANDLE hIvasDec, int16_t *pcmBuf );
+#ifdef FIX_FMSW_DEC
+static ivas_error decodeVoIP( DecArguments arg, BS_READER_HANDLE hBsReader, IVAS_DEC_HRTF_BINARY_WRAPPER *hHrtf, RotFileReader *headRotReader, RotFileReader *externalOrientationFileReader, RotFileReader *refRotReader, Vector3PairFileReader *referenceVectorReader, ObjectEditFileReader *objectEditFileReader, ISAR_SPLIT_REND_BITS_DATA *splitRendBits, IVAS_DEC_HANDLE *phIvasDec, int16_t *pcmBuf );
+#else
 static ivas_error decodeVoIP( DecArguments arg, BS_READER_HANDLE hBsReader, IVAS_DEC_HRTF_BINARY_WRAPPER *hHrtf, RotFileReader *headRotReader, RotFileReader *externalOrientationFileReader, RotFileReader *refRotReader, Vector3PairFileReader *referenceVectorReader, ObjectEditFileReader *objectEditFileReader, ISAR_SPLIT_REND_BITS_DATA *splitRendBits, IVAS_RENDER_CONFIG_DATA *renderConfig, IVAS_DEC_HANDLE *phIvasDec, int16_t *pcmBuf );
+#endif
 static ivas_error load_hrtf_from_file( IVAS_DEC_HRTF_BINARY_WRAPPER *hHrtfBinary, IVAS_DEC_HANDLE hIvasDec, const IVAS_AUDIO_CONFIG OutputConfig, const int32_t output_Fs );
 #ifdef DEBUGGING
 static ivas_error printBitstreamInfoVoip( DecArguments arg, BS_READER_HANDLE hBsReader, IVAS_DEC_HANDLE hIvasDec );
 static int16_t app_own_random( int16_t *seed );
 #endif
 static void do_object_editing( IVAS_EDITABLE_PARAMETERS *editableParameters, ObjectEditFileReader *objectEditFileReader );
+#ifdef FIX_FMSW_DEC
+static ivas_error restartDecoder( IVAS_DEC_HANDLE *phIvasDec, const IVAS_DEC_MODE decMode, DecArguments *arg );
+#else
 static ivas_error restartDecoder( IVAS_DEC_HANDLE *phIvasDec, const IVAS_DEC_MODE decMode, DecArguments *arg, IVAS_RENDER_CONFIG_DATA *renderConfig, IVAS_CUSTOM_LS_DATA *hLsCustomData );
+#endif
 
 
 /*------------------------------------------------------------------------------------------*
@@ -775,7 +783,11 @@ int main(
 
     if ( arg.voipMode )
     {
+#ifdef FIX_FMSW_DEC
+        error = decodeVoIP( arg, hBsReader, &hHrtfBinary, headRotReader, externalOrientationFileReader, refRotReader, referenceVectorReader, objectEditFileReader, &splitRendBits, &hIvasDec, pcmBuf );
+#else
         error = decodeVoIP( arg, hBsReader, &hHrtfBinary, headRotReader, externalOrientationFileReader, refRotReader, referenceVectorReader, objectEditFileReader, &splitRendBits, &renderConfig, &hIvasDec, pcmBuf );
+#endif
     }
     else
     {
@@ -3165,7 +3177,9 @@ static ivas_error decodeVoIP(
     Vector3PairFileReader *referenceVectorReader,
     ObjectEditFileReader *objectEditFileReader,
     ISAR_SPLIT_REND_BITS_DATA *splitRendBits,
+#ifndef FIX_FMSW_DEC
     IVAS_RENDER_CONFIG_DATA *renderConfig,
+#endif
     IVAS_DEC_HANDLE *phIvasDec,
     int16_t *pcmBuf )
 {
@@ -3357,6 +3371,9 @@ static ivas_error decodeVoIP(
         if ( ivasRtp.restartNeeded )
         {
             IVAS_DEC_MODE newDecModeInPacket = ( ivasRtp.codecId == IVAS_RTP_EVS ) ? IVAS_DEC_MODE_EVS : IVAS_DEC_MODE_IVAS;
+#ifdef FIX_FMSW_DEC
+            if ( ( error = restartDecoder( &hIvasDec, newDecModeInPacket, &arg ) ) != IVAS_ERR_OK )
+#else
             if ( ( error = restartDecoder(
                        &hIvasDec,
                        newDecModeInPacket,
@@ -3364,6 +3381,7 @@ static ivas_error decodeVoIP(
                        renderConfig,
                        NULL /* ToDo : Provide LS Custom Data */
                        ) ) != IVAS_ERR_OK )
+#endif
             {
                 fprintf( stderr, "\nFailed to restart decoder from %d to %d\n", arg.decMode, newDecModeInPacket );
                 goto cleanup;
@@ -3609,6 +3627,9 @@ static ivas_error decodeVoIP(
                     }
 
                     IVAS_DEC_MODE newDecModeInPacket = ( tempBsFormat == IVAS_DEC_BS_MONO ) ? IVAS_DEC_MODE_EVS : IVAS_DEC_MODE_IVAS;
+#ifdef FIX_FMSW_DEC
+                    if ( ( error = restartDecoder( &hIvasDec, newDecModeInPacket, &arg ) ) != IVAS_ERR_OK )
+#else
                     if ( ( error = restartDecoder(
                                &hIvasDec,
                                newDecModeInPacket,
@@ -3616,6 +3637,7 @@ static ivas_error decodeVoIP(
                                NULL, /* ToDo : Provide rendererConfig */
                                NULL  /* ToDo : Provide LS Custom Data */
                                ) ) != IVAS_ERR_OK )
+#endif
                     {
                         fprintf( stderr, "\nFailed to restart decoder\n" );
                         goto cleanup;
@@ -4318,12 +4340,18 @@ static ivas_error load_hrtf_from_file(
 static ivas_error restartDecoder(
     IVAS_DEC_HANDLE *phIvasDec,
     const IVAS_DEC_MODE decMode,
-    DecArguments *arg,
+    DecArguments *arg
+#ifndef FIX_FMSW_DEC
+    ,
     IVAS_RENDER_CONFIG_DATA *renderConfig,
-    IVAS_CUSTOM_LS_DATA *hLsCustomData )
+    IVAS_CUSTOM_LS_DATA *hLsCustomData
+#endif
+)
 {
     ivas_error error = IVAS_ERR_OK;
+#ifndef FIX_FMSW_DEC
     IVAS_DEC_HANDLE hIvasDec;
+#endif
 
     if ( phIvasDec == NULL )
     {
@@ -4343,6 +4371,7 @@ static ivas_error restartDecoder(
 
     arg->decMode = decMode;
 
+#ifndef FIX_FMSW_DEC
     hIvasDec = *phIvasDec;
 
     uint16_t aeID = arg->aeSequence.count > 0 ? arg->aeSequence.pID[0] : IVAS_DEFAULT_AEID;
@@ -4405,11 +4434,12 @@ static ivas_error restartDecoder(
             goto cleanup;
         }
     }
-
+#endif
     return IVAS_ERR_OK;
 
 cleanup:
     IVAS_DEC_Close( phIvasDec );
+
     return error;
 }
 
diff --git a/lib_com/ivas_prot.h b/lib_com/ivas_prot.h
index 3201fd15bdb53daef1a7643fb2d9a0f98dbe5814..358d6535afc5fdd914b1c14bccef9d12cbc74b28 100755
--- a/lib_com/ivas_prot.h
+++ b/lib_com/ivas_prot.h
@@ -434,7 +434,11 @@ void destroy_core_dec(
 );
 
 void ivas_destroy_dec(
+#ifdef FIX_FMSW_DEC
+    Decoder_Struct **st_ivas                                    /* i/o: IVAS decoder structure                  */
+#else
     Decoder_Struct *st_ivas                                     /* i/o: IVAS decoder structure                  */
+#endif
 );
 
 void ivas_initialize_handles_dec(
diff --git a/lib_com/options.h b/lib_com/options.h
index bbea3aa1534059d14c1f9b80304d8ebe81ea7d42..a44133370901ba18364e59d1f888fe56e5e2c3eb 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -169,6 +169,7 @@
 /* any switch which is non-be wrt. TS 26.258 V3.0 */
 
 #define FIX_1543_MID_LSF_BITS                           /* VA: float issue 1543: Resolve "MSAN: use-of-uninitialized-value in lib_enc/lsf_enc.c:262:5 for EVS encoder" */
+#define FIX_FMSW_DEC                                    /* float issue 1542: fix JBM issue in format switching */
 
 
 /* ##################### End NON-BE switches ########################### */
diff --git a/lib_dec/ivas_init_dec.c b/lib_dec/ivas_init_dec.c
index b16a3160419d38c48b3543873cb459e3c23f222c..afbc724581c85b9237b75e8a044fade5296b285c 100644
--- a/lib_dec/ivas_init_dec.c
+++ b/lib_dec/ivas_init_dec.c
@@ -1277,7 +1277,11 @@ ivas_error ivas_init_decoder_front(
      * Allocate and initialize Custom loudspeaker layout handle
      *--------------------------------------------------------------------*/
 
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->hDecoderConfig->Opt_LsCustom && st_ivas->hLsSetupCustom == NULL )
+#else
     if ( st_ivas->hDecoderConfig->Opt_LsCustom )
+#endif
     {
         if ( ( error = ivas_ls_custom_open( &( st_ivas->hLsSetupCustom ) ) ) != IVAS_ERR_OK )
         {
@@ -1289,7 +1293,11 @@ ivas_error ivas_init_decoder_front(
      * Allocate and initialize Head-Tracking handle
      *--------------------------------------------------------------------*/
 
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->hDecoderConfig->Opt_Headrotation && st_ivas->hHeadTrackData == NULL )
+#else
     if ( st_ivas->hDecoderConfig->Opt_Headrotation )
+#endif
     {
         if ( ( error = ivas_headTrack_open( &( st_ivas->hHeadTrackData ) ) ) != IVAS_ERR_OK )
         {
@@ -1305,7 +1313,11 @@ ivas_error ivas_init_decoder_front(
      * Allocate and initialize external orientation handle
      *--------------------------------------------------------------------*/
 
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->hDecoderConfig->Opt_ExternalOrientation && st_ivas->hExtOrientationData == NULL )
+#else
     if ( st_ivas->hDecoderConfig->Opt_ExternalOrientation )
+#endif
     {
         if ( ( error = ivas_external_orientation_open( &( st_ivas->hExtOrientationData ), st_ivas->hDecoderConfig->render_num_subframes ) ) != IVAS_ERR_OK )
         {
@@ -1317,7 +1329,11 @@ ivas_error ivas_init_decoder_front(
      * Allocate and initialize combined orientation handle
      *--------------------------------------------------------------------*/
 
+#ifdef FIX_FMSW_DEC
+    if ( ( st_ivas->hDecoderConfig->Opt_Headrotation || st_ivas->hDecoderConfig->Opt_ExternalOrientation ) && st_ivas->hCombinedOrientationData == NULL )
+#else
     if ( st_ivas->hDecoderConfig->Opt_Headrotation || st_ivas->hDecoderConfig->Opt_ExternalOrientation )
+#endif
     {
         if ( ( error = ivas_combined_orientation_open( &( st_ivas->hCombinedOrientationData ), st_ivas->hDecoderConfig->output_Fs, st_ivas->hDecoderConfig->render_num_subframes ) ) != IVAS_ERR_OK )
         {
@@ -1329,8 +1345,14 @@ ivas_error ivas_init_decoder_front(
      * Allocate and initialize Binaural Renderer configuration handle
      *--------------------------------------------------------------------*/
 
+#ifdef FIX_FMSW_DEC
+    if ( ( st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_ROOM_IR || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_ROOM_REVERB || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_SPLIT_CODED || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_SPLIT_PCM ||
+           ( st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_STEREO && st_ivas->hDecoderConfig->Opt_non_diegetic_pan ) ) &&
+         st_ivas->hRenderConfig == NULL )
+#else
     if ( st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_ROOM_IR || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_ROOM_REVERB || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_SPLIT_CODED || st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_BINAURAL_SPLIT_PCM ||
          ( st_ivas->hDecoderConfig->output_config == IVAS_AUDIO_CONFIG_STEREO && st_ivas->hDecoderConfig->Opt_non_diegetic_pan ) )
+#endif
     {
         if ( ( error = ivas_render_config_open( &( st_ivas->hRenderConfig ) ) ) != IVAS_ERR_OK )
         {
@@ -2739,9 +2761,16 @@ void ivas_initialize_handles_dec(
         st_ivas->hCPE[i] = NULL;
     }
 
-    st_ivas->bit_stream = NULL;
-    st_ivas->mem_hp20_out = NULL;
-    st_ivas->hLimiter = NULL;
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->restartNeeded == 0 )
+    {
+#endif
+        st_ivas->bit_stream = NULL;
+        st_ivas->mem_hp20_out = NULL;
+        st_ivas->hLimiter = NULL;
+#ifdef FIX_FMSW_DEC
+    }
+#endif
 
     /* ISM metadata handles */
     for ( i = 0; i < MAX_NUM_OBJECTS; i++ )
@@ -2784,14 +2813,21 @@ void ivas_initialize_handles_dec(
     st_ivas->hMasaIsmData = NULL;
     st_ivas->hSbaIsmData = NULL;
 
-    st_ivas->hHeadTrackData = NULL;
-    st_ivas->hHrtfTD = NULL;
-    st_ivas->hLsSetupCustom = NULL;
-    st_ivas->hRenderConfig = NULL;
-    st_ivas->hExtOrientationData = NULL;
-    st_ivas->hCombinedOrientationData = NULL;
-    st_ivas->acousticEnvironmentsCount = 0;
-    st_ivas->pAcousticEnvironments = NULL;
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->restartNeeded == 0 )
+    {
+#endif
+        st_ivas->hHeadTrackData = NULL;
+        st_ivas->hHrtfTD = NULL;
+        st_ivas->hLsSetupCustom = NULL;
+        st_ivas->hRenderConfig = NULL;
+        st_ivas->hExtOrientationData = NULL;
+        st_ivas->hCombinedOrientationData = NULL;
+        st_ivas->acousticEnvironmentsCount = 0;
+        st_ivas->pAcousticEnvironments = NULL;
+#ifdef FIX_FMSW_DEC
+    }
+#endif
 
     st_ivas->hSplitBinRend = NULL;
     for ( i = 0; i < MAX_HEAD_ROT_POSES - 1; ++i )
@@ -2819,10 +2855,17 @@ void ivas_initialize_handles_dec(
  *-------------------------------------------------------------------------*/
 
 void ivas_destroy_dec(
+#ifdef FIX_FMSW_DEC
+    Decoder_Struct **st_ivas_out /* i/o: IVAS decoder handle      */
+#else
     Decoder_Struct *st_ivas /* i/o: IVAS decoder handle      */
+#endif
 )
 {
     int16_t i;
+#ifdef FIX_FMSW_DEC
+    Decoder_Struct *st_ivas = *st_ivas_out;
+#endif
 
     /* CLDFB handles */
     for ( i = 0; i < MAX_INTERN_CHANNELS; i++ )
@@ -2867,17 +2910,24 @@ void ivas_destroy_dec(
         }
     }
 
-    /* HP20 filter handles */
-    if ( st_ivas->mem_hp20_out != NULL )
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->restartNeeded == 0 )
     {
-        for ( i = 0; i < getNumChanSynthesis( st_ivas ); i++ )
+#endif
+        /* HP20 filter handles */
+        if ( st_ivas->mem_hp20_out != NULL )
         {
-            free( st_ivas->mem_hp20_out[i] );
-            st_ivas->mem_hp20_out[i] = NULL;
+            for ( i = 0; i < getNumChanSynthesis( st_ivas ); i++ )
+            {
+                free( st_ivas->mem_hp20_out[i] );
+                st_ivas->mem_hp20_out[i] = NULL;
+            }
+            free( st_ivas->mem_hp20_out );
+            st_ivas->mem_hp20_out = NULL;
         }
-        free( st_ivas->mem_hp20_out );
-        st_ivas->mem_hp20_out = NULL;
+#ifdef FIX_FMSW_DEC
     }
+#endif
 
     /* ISM metadata handles */
     ivas_ism_metadata_close( st_ivas->hIsmMetaData, 0 );
@@ -2952,12 +3002,19 @@ void ivas_destroy_dec(
     /* LS config converter handle */
     ivas_ls_setup_conversion_close( &st_ivas->hLsSetUpConversion );
 
-    /* Custom LS configuration handle */
-    if ( st_ivas->hLsSetupCustom != NULL )
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->restartNeeded == 0 )
     {
-        free( st_ivas->hLsSetupCustom );
-        st_ivas->hLsSetupCustom = NULL;
+#endif
+        /* Custom LS configuration handle */
+        if ( st_ivas->hLsSetupCustom != NULL )
+        {
+            free( st_ivas->hLsSetupCustom );
+            st_ivas->hLsSetupCustom = NULL;
+        }
+#ifdef FIX_FMSW_DEC
     }
+#endif
 
     /* Mono downmix structure */
     ivas_mono_dmx_renderer_close( &st_ivas->hMonoDmxRenderer );
@@ -2994,25 +3051,40 @@ void ivas_destroy_dec(
     /* HRTF statistics */
     ivas_HRTF_statistics_binary_close( &st_ivas->hHrtfStatistics );
 
-    /* Config. Renderer */
-    ivas_render_config_close( &( st_ivas->hRenderConfig ) );
-
-    /* Acoustic environments */
-    if ( st_ivas->pAcousticEnvironments != NULL )
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->restartNeeded == 0 )
     {
-        free( st_ivas->pAcousticEnvironments );
-        st_ivas->pAcousticEnvironments = NULL;
-    }
+#endif
+        /* Config. Renderer */
+        ivas_render_config_close( &( st_ivas->hRenderConfig ) );
 
-    /* Limiter struct */
-    ivas_limiter_close( &( st_ivas->hLimiter ) );
+        /* Acoustic environments */
+        if ( st_ivas->pAcousticEnvironments != NULL )
+        {
+            free( st_ivas->pAcousticEnvironments );
+            st_ivas->pAcousticEnvironments = NULL;
+        }
+
+        /* Limiter struct */
+        ivas_limiter_close( &( st_ivas->hLimiter ) );
 
-    /* Decoder configuration structure */
-    if ( st_ivas->hDecoderConfig != NULL )
+        /* Decoder configuration structure */
+        if ( st_ivas->hDecoderConfig != NULL )
+        {
+            free( st_ivas->hDecoderConfig );
+            st_ivas->hDecoderConfig = NULL;
+        }
+#ifdef FIX_FMSW_DEC
+    }
+    else
     {
-        free( st_ivas->hDecoderConfig );
-        st_ivas->hDecoderConfig = NULL;
+        /* resets in case of format switching */
+        st_ivas->nchan_ism = 0;
+        st_ivas->ism_mode = ISM_MODE_NONE;
+        st_ivas->mc_mode = MC_MODE_NONE;
+        st_ivas->sba_dirac_stereo_flag = 0;
     }
+#endif
 
     /* TC buffer structure */
     ivas_dec_tc_buffer_close( &st_ivas->hTcBuffer );
@@ -3030,7 +3102,15 @@ void ivas_destroy_dec(
     }
 
     /* main IVAS handle */
+#ifdef FIX_FMSW_DEC
+    if ( st_ivas->restartNeeded == 0 )
+    {
+        free( *st_ivas_out );
+        *st_ivas_out = NULL;
+    }
+#else
     free( st_ivas );
+#endif
 
     return;
 }
diff --git a/lib_dec/lib_dec.c b/lib_dec/lib_dec.c
index 0afec7310f1d418fba7b53751caff22a671d131a..7ba049791e91b1d7ef04456fc1116628c01efaf8 100644
--- a/lib_dec/lib_dec.c
+++ b/lib_dec/lib_dec.c
@@ -150,68 +150,83 @@ ivas_error IVAS_DEC_Open(
         return IVAS_ERR_UNEXPECTED_NULL_POINTER;
     }
 
-    /*-----------------------------------------------------------------*
-     * Allocate and initialize IVAS application decoder handle
-     *-----------------------------------------------------------------*/
-
-    if ( ( *phIvasDec = (IVAS_DEC_HANDLE) malloc( sizeof( struct IVAS_DEC ) ) ) == NULL )
+#ifdef FIX_FMSW_DEC
+    if ( ( *phIvasDec ) != NULL && ( *phIvasDec )->st_ivas != NULL && ( *phIvasDec )->st_ivas->restartNeeded != 0 )
     {
-        return IVAS_ERROR( IVAS_ERR_FAILED_ALLOC, "Cannot allocate memory for IVAS decoder handle" );
+        hIvasDec = *phIvasDec;
+
+        st_ivas = hIvasDec->st_ivas;
     }
+    else
+    {
+#endif
+        /*-----------------------------------------------------------------*
+         * Allocate and initialize IVAS application decoder handle
+         *-----------------------------------------------------------------*/
 
-    hIvasDec = *phIvasDec;
-    hIvasDec->hVoIP = NULL;
-    hIvasDec->hTimeScaler = NULL;
-    hIvasDec->tsm_scale = 100;
-    hIvasDec->tsm_max_scaling = 0;
-    hIvasDec->tsm_quality = 1.0f;
-    hIvasDec->timeScalingDone = 0;
-    hIvasDec->needNewFrame = false;
-    hIvasDec->nTransportChannelsOld = 0;
-    hIvasDec->nSamplesAvailableNext = 0;
-    hIvasDec->nSamplesFrame = 0;
-    hIvasDec->hasBeenFedFrame = false;
-    hIvasDec->hasBeenFedFirstGoodFrame = false;
-    hIvasDec->hasDecodedFirstGoodFrame = false;
-    hIvasDec->isInitialized = false;
-    hIvasDec->updateOrientation = false;
-    hIvasDec->flushbuffer = NULL;
-    hIvasDec->pcmType = IVAS_DEC_PCM_INVALID;
-    hIvasDec->nSamplesFlushed = 0;
-    hIvasDec->hasBeenPreparedRendering = false;
+        if ( ( *phIvasDec = (IVAS_DEC_HANDLE) malloc( sizeof( struct IVAS_DEC ) ) ) == NULL )
+        {
+            return IVAS_ERROR( IVAS_ERR_FAILED_ALLOC, "Cannot allocate memory for IVAS decoder handle" );
+        }
 
-    hIvasDec->mode = mode;
+        hIvasDec = *phIvasDec;
+        hIvasDec->hVoIP = NULL;
+        hIvasDec->hTimeScaler = NULL;
+        hIvasDec->tsm_scale = 100;
+        hIvasDec->tsm_max_scaling = 0;
+        hIvasDec->tsm_quality = 1.0f;
+        hIvasDec->timeScalingDone = 0;
+        hIvasDec->needNewFrame = false;
+        hIvasDec->nTransportChannelsOld = 0;
+        hIvasDec->nSamplesAvailableNext = 0;
+        hIvasDec->nSamplesFrame = 0;
+        hIvasDec->hasBeenFedFrame = false;
+        hIvasDec->hasBeenFedFirstGoodFrame = false;
+        hIvasDec->hasDecodedFirstGoodFrame = false;
+        hIvasDec->isInitialized = false;
+        hIvasDec->updateOrientation = false;
+        hIvasDec->flushbuffer = NULL;
+        hIvasDec->pcmType = IVAS_DEC_PCM_INVALID;
+        hIvasDec->nSamplesFlushed = 0;
+        hIvasDec->hasBeenPreparedRendering = false;
 
-    hIvasDec->bitstreamformat = G192;
+        hIvasDec->mode = mode;
+
+        hIvasDec->bitstreamformat = G192;
 #ifdef DEBUGGING
-    hIvasDec->Opt_VOIP = 0;
+        hIvasDec->Opt_VOIP = 0;
 #endif
-    hIvasDec->amrwb_rfc4867_flag = -1;
-    hIvasDec->prev_ft_speech = 1; /* RXDTX handler previous frametype flag for G.192 format AMRWB SID_FIRST detection */
-    hIvasDec->CNG = 0;            /* RXDTX handler CNG = 1, no CNG = 0*/
+        hIvasDec->amrwb_rfc4867_flag = -1;
+        hIvasDec->prev_ft_speech = 1; /* RXDTX handler previous frametype flag for G.192 format AMRWB SID_FIRST detection */
+        hIvasDec->CNG = 0;            /* RXDTX handler CNG = 1, no CNG = 0*/
 
-    /*-----------------------------------------------------------------*
-     * Initialize IVAS-codec decoder state
-     *-----------------------------------------------------------------*/
+        /*-----------------------------------------------------------------*
+         * Initialize IVAS-codec decoder state
+         *-----------------------------------------------------------------*/
 
-    if ( ( hIvasDec->st_ivas = (Decoder_Struct *) malloc( sizeof( Decoder_Struct ) ) ) == NULL )
-    {
-        return IVAS_ERROR( IVAS_ERR_FAILED_ALLOC, "Cannot allocate memory for IVAS decoder structure" );
-    }
+        if ( ( hIvasDec->st_ivas = (Decoder_Struct *) malloc( sizeof( Decoder_Struct ) ) ) == NULL )
+        {
+            return IVAS_ERROR( IVAS_ERR_FAILED_ALLOC, "Cannot allocate memory for IVAS decoder structure" );
+        }
 
-    if ( ( hIvasDec->st_ivas->hDecoderConfig = (DECODER_CONFIG_HANDLE) malloc( sizeof( DECODER_CONFIG ) ) ) == NULL )
-    {
-        return IVAS_ERROR( IVAS_ERR_FAILED_ALLOC, "Cannot allocate memory for Decoder config structure" );
-    }
+        if ( ( hIvasDec->st_ivas->hDecoderConfig = (DECODER_CONFIG_HANDLE) malloc( sizeof( DECODER_CONFIG ) ) ) == NULL )
+        {
+            return IVAS_ERROR( IVAS_ERR_FAILED_ALLOC, "Cannot allocate memory for Decoder config structure" );
+        }
 
-    /*-----------------------------------------------------------------*
-     * Initialize IVAS-codec decoder state
-     *-----------------------------------------------------------------*/
+        /*-----------------------------------------------------------------*
+         * Initialize IVAS-codec decoder state
+         *-----------------------------------------------------------------*/
 
-    st_ivas = hIvasDec->st_ivas;
+        st_ivas = hIvasDec->st_ivas;
 
-    /* initialize Decoder Config. handle */
-    init_decoder_config( hIvasDec->st_ivas->hDecoderConfig );
+        /* initialize Decoder Config. handle */
+        init_decoder_config( hIvasDec->st_ivas->hDecoderConfig );
+
+#ifdef FIX_FMSW_DEC
+        hIvasDec->st_ivas->restartNeeded = 0;
+    }
+#endif
 
     /* initialize pointers to handles to NULL */
     ivas_initialize_handles_dec( st_ivas );
@@ -336,7 +351,11 @@ void IVAS_DEC_Close(
         return;
     }
 
+#ifdef FIX_FMSW_DEC
+    if ( ( *phIvasDec )->st_ivas->restartNeeded == 0 && ( *phIvasDec )->hVoIP )
+#else
     if ( ( *phIvasDec )->hVoIP )
+#endif
     {
         ivas_destroy_handle_VoIP( ( *phIvasDec )->hVoIP );
         ( *phIvasDec )->hVoIP = NULL;
@@ -348,20 +367,38 @@ void IVAS_DEC_Close(
         ivas_destroy_handle_isar( &( *phIvasDec )->st_ivas->hSplitBinRend );
 
         /* destroy IVAS decoder handles */
+#ifdef FIX_FMSW_DEC
+        ivas_destroy_dec( &( *phIvasDec )->st_ivas );
+#else
         ivas_destroy_dec( ( *phIvasDec )->st_ivas );
-        ( *phIvasDec )->st_ivas = NULL;
+#ifdef FIX_FMSW_DEC
+        if ( ( *phIvasDec )->st_ivas->restartNeeded == 0 )
+        {
+#endif
+            ( *phIvasDec )->st_ivas = NULL;
+#ifdef FIX_FMSW_DEC
+        }
+#endif
+#endif
     }
 
-    apa_exit( &( *phIvasDec )->hTimeScaler );
-
-    if ( ( *phIvasDec )->flushbuffer != NULL )
+#ifdef FIX_FMSW_DEC
+    if ( ( *phIvasDec )->st_ivas == NULL || ( *phIvasDec )->st_ivas->restartNeeded == 0 )
     {
-        free( ( *phIvasDec )->flushbuffer );
-    }
+#endif
+        apa_exit( &( *phIvasDec )->hTimeScaler );
+
+        if ( ( *phIvasDec )->flushbuffer != NULL )
+        {
+            free( ( *phIvasDec )->flushbuffer );
+        }
 
-    free( *phIvasDec );
-    *phIvasDec = NULL;
-    phIvasDec = NULL;
+        free( *phIvasDec );
+        *phIvasDec = NULL;
+        phIvasDec = NULL;
+#ifdef FIX_FMSW_DEC
+    }
+#endif
 
     return;
 }
diff --git a/lib_util/ivas_rtp_api.h b/lib_util/ivas_rtp_api.h
index 6b23bd04e8ba77475d919976aa83b48da5988eec..0b2731ed39dce0a037b4589695abfebf4348db95 100644
--- a/lib_util/ivas_rtp_api.h
+++ b/lib_util/ivas_rtp_api.h
@@ -82,6 +82,9 @@
 /* IVAS Codec Types */
 typedef enum
 {
+#ifdef FIX_FMSW_DEC
+    IVAS_RTP_UNDEF, /* undefined = Codec Type not set yet */
+#endif
     IVAS_RTP_EVS, /* EVS  */
     IVAS_RTP_IVAS /* IVAS */
 } IVAS_RTP_CODEC;
diff --git a/lib_util/ivas_rtp_file.c b/lib_util/ivas_rtp_file.c
index 35733681c0249f1e198c3db1d2b994eb125659d0..679728b924ca4536a679cd1e07c1effba95fa864 100644
--- a/lib_util/ivas_rtp_file.c
+++ b/lib_util/ivas_rtp_file.c
@@ -867,6 +867,9 @@ ivas_error IVAS_RTP_READER_Init(
     rtp->unpackCfg.maxFramesPerPacket = IVAS_MAX_FRAMES_PER_RTP_PACKET;
     rtp->rtpPacket.buffer = rtp->packet;
     rtp->rtpPacket.capacity = sizeof( rtp->packet );
+#ifdef FIX_FMSW_DEC
+    rtp->codecId = IVAS_RTP_UNDEF;
+#endif
 
     error = IVAS_RTP_UNPACK_Open( &rtp->hUnpack, &rtp->unpackCfg );
     if ( error == IVAS_ERR_OK )
@@ -1041,15 +1044,19 @@ ivas_error IVAS_RTP_ReadNextFrame(
     }
     else
     {
+#ifdef FIX_FMSW_DEC
+        if ( ( codecId != IVAS_RTP_UNDEF ) && ( ( rtp->codecId != codecId ) || ( codecId == IVAS_RTP_EVS && ( rtp->isAMRWB_IOmode != isAMRWB_IOmode ) ) ) )
+#else
         rtp->restartNeeded = ( rtp->codecId != codecId ) ||
                              ( codecId == IVAS_RTP_EVS && ( rtp->isAMRWB_IOmode != isAMRWB_IOmode ) );
+#endif
 
-        if ( rtp->restartNeeded )
-        {
-            fprintf( stdout, "\nRTP packet codec changed %s -> %s\n",
-                     ( rtp->codecId == IVAS_RTP_EVS ) ? ( rtp->isAMRWB_IOmode ? "AMRWB_IO" : "EVS" ) : "IVAS",
-                     ( codecId == IVAS_RTP_EVS ) ? ( isAMRWB_IOmode ? "AMRWB_IO" : "EVS" ) : "IVAS" );
-        }
+            if ( rtp->restartNeeded )
+            {
+                fprintf( stdout, "\nRTP packet codec changed %s -> %s\n",
+                         ( rtp->codecId == IVAS_RTP_EVS ) ? ( rtp->isAMRWB_IOmode ? "AMRWB_IO" : "EVS" ) : "IVAS",
+                         ( codecId == IVAS_RTP_EVS ) ? ( isAMRWB_IOmode ? "AMRWB_IO" : "EVS" ) : "IVAS" );
+            }
 
         rtp->codecId = codecId;
         rtp->isAMRWB_IOmode = isAMRWB_IOmode;