diff --git a/lib_com/ivas_cnst.h b/lib_com/ivas_cnst.h
index c2d42d0c66d4bdcdbdd46e4b558a382b3da01f3e..e17b4a72da18eb41f5529a48e4504a5525a38ae8 100755
--- a/lib_com/ivas_cnst.h
+++ b/lib_com/ivas_cnst.h
@@ -1582,14 +1582,22 @@ typedef enum
 typedef enum
 {
     TDREND_POSTYPE_ABSOLUTE,                                                /* The source position is in absolute coordinates  */
+#ifdef FIX_550_FIRST_FRAME_ACCESS_ALT
+    TDREND_POSTYPE_NON_DIEGETIC                                             /* The source position is non-diegetic */
+#else
     TDREND_POSTYPE_RELATIVE_TO_LISTENER                                     /* The source position is relative to the listener */
+#endif
 } TDREND_PosType_t;
 
 typedef enum
 {
     TDREND_PLAYSTATUS_INITIAL,
+#ifndef FIX_550_FIRST_FRAME_ACCESS_ALT
     TDREND_PLAYSTATUS_PLAYING,
     TDREND_PLAYSTATUS_PLAYING_NON_DIEGETIC
+#else
+    TDREND_PLAYSTATUS_PLAYING
+#endif
 } TDREND_PlayStatus_t;
 
 typedef enum
diff --git a/lib_com/options.h b/lib_com/options.h
old mode 100644
new mode 100755
index 57154a5247317f173da542056b27465d6742be83..c7204c05fad403821b5f831a45e0020853e976df
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -163,6 +163,8 @@
 #define FIX_UNCLR_ISSUE                                 /* VoiceAge: issue 574: Fix UNCLR mis-classifications in noisy speech stereo */
 #define FIX_TCX_LOWRATE_LIMITATION                      /* VA: issue 577: TCX bitrate limitation only when DEBUGGING is active */
 #define FIX_575_LOW_OVERLAP_PLC_RECOVERY                /* FhG: Issue 575 fix for PLC and transistion to TCX5*/
+#define FIX_550_FIRST_FRAME_ACCESS                      /* Eri: Issue 550: TD Object renderer: first frame accesses wrong transport channel offsets */
+#define FIX_550_FIRST_FRAME_ACCESS_ALT                  /* Eri: Issue 550: Should be merged with FIX_550_FIRST_FRAME_ACCESS above, or accepted at the same time */
 #define FIX_569_TD_FILTER_LENGTH                        /* Eri: Issue 569: If an HRTF binary file exceeds the SFX_SPAT_BIN_MAX_FILTER_LENGTH the decoder crashes. This truncates the filter when generated from the model.  */
 #define ISM_FB_16k4                                     /* VA: Issue: 579: change BW from SWB to FB in NxISM conditions to match the EVS codec */
 #define FIX_580_PARAMMC_ENER_BURSTS                     /* FhG: issue 580: energy bursts due to ILD holding when energy relations change too much */
diff --git a/lib_rend/ivas_objectRenderer.c b/lib_rend/ivas_objectRenderer.c
index 2ba225b2f15723187a77c6c8ca5404f7526e366b..1c035d377dc8ec24d7d434c1009d9ed22acb5e4f 100644
--- a/lib_rend/ivas_objectRenderer.c
+++ b/lib_rend/ivas_objectRenderer.c
@@ -291,6 +291,21 @@ ivas_error ivas_td_binaural_renderer_unwrap(
             hBinRendererTd->Sources[c_indx]->SrcRend_p->InputAvailable = TRUE;
             c_indx++;
         }
+#ifndef FIX_550_FIRST_FRAME_ACCESS_ALT
+#ifdef FIX_550_FIRST_FRAME_ACCESS
+        if ( ivas_format == ISM_FORMAT )
+        {
+            if ( hIsmMetaData[nS]->non_diegetic_flag )
+            {
+                TDREND_MIX_SRC_SetPlayState( hBinRendererTd, nS, TDREND_PLAYSTATUS_PLAYING_NON_DIEGETIC );
+            }
+            else
+            {
+                TDREND_MIX_SRC_SetPlayState( hBinRendererTd, nS, TDREND_PLAYSTATUS_PLAYING );
+            }
+        }
+#endif
+#endif
     }
 
     for ( subframe_idx = 0; subframe_idx < MAX_PARAM_SPATIAL_SUBFRAMES; subframe_idx++ )
@@ -316,6 +331,19 @@ ivas_error ivas_td_binaural_renderer_unwrap(
         {
             return error;
         }
+
+#ifdef FIX_550_FIRST_FRAME_ACCESS
+        /* Advance subframe pointer */
+        c_indx = 0;
+        for ( nS = 0; nS < num_src; nS++ )
+        {
+            if ( !( ivas_format == MC_FORMAT && nS == lfe_idx ) ) /* Skip LFE for MC */
+            {
+                hBinRendererTd->Sources[c_indx]->InputFrame_p += subframe_length;
+                c_indx++;
+            }
+        }
+#endif
     }
 
     if ( hReverb != NULL )
@@ -352,7 +380,9 @@ ivas_error TDREND_GetMix(
     float hrf_left_delta[SFX_SPAT_BIN_MAX_FILTER_LENGTH];
     float hrf_right_delta[SFX_SPAT_BIN_MAX_FILTER_LENGTH];
     int16_t intp_count;
+#ifndef FIX_550_FIRST_FRAME_ACCESS_ALT
     float pan_left, pan_right;
+#endif
     int16_t subframe_update_flag;
 
     subframe_update_flag = subframe_idx == ism_md_subframe_update;
@@ -389,13 +419,20 @@ ivas_error TDREND_GetMix(
             error = TDREND_REND_RenderSourceHRFilt( Src_p, hrf_left_delta, hrf_right_delta, intp_count, output_buf, subframe_length );
         }
 
+#ifndef FIX_550_FIRST_FRAME_ACCESS_ALT
         if ( ( SrcRend_p->InputAvailable == TRUE ) && ( SrcRend_p->PlayStatus == TDREND_PLAYSTATUS_PLAYING_NON_DIEGETIC ) )
         {
             pan_left = ( SrcSpatial_p->Pos_p[1] + 1.f ) * 0.5f;
             pan_right = 1.f - pan_left;
+#ifdef FIX_550_FIRST_FRAME_ACCESS
+            v_multc_acc( Src_p->InputFrame_p, pan_left, output_buf[0], subframe_length );
+            v_multc_acc( Src_p->InputFrame_p, pan_right, output_buf[1], subframe_length );
+#else
             v_multc_acc( &Src_p->InputFrame_p[subframe_idx * subframe_length], pan_left, output_buf[0], subframe_length );
             v_multc_acc( &Src_p->InputFrame_p[subframe_idx * subframe_length], pan_right, output_buf[1], subframe_length );
+#endif
         }
+#endif
     }
 
     /* Populate output variable */
@@ -472,11 +509,23 @@ void TDREND_Update_object_positions(
                 Pos[1] = hIsmMetaData[nS]->azimuth / 90.f;
                 Pos[2] = 0;
                 TDREND_MIX_SRC_SetPos( hBinRendererTd, nS, Pos );
+#ifdef FIX_550_FIRST_FRAME_ACCESS_ALT
+                hBinRendererTd->Sources[nS]->SrcSpatial_p->PosType = TDREND_POSTYPE_NON_DIEGETIC;
+#else
+#ifndef FIX_550_FIRST_FRAME_ACCESS
                 TDREND_MIX_SRC_SetPlayState( hBinRendererTd, nS, TDREND_PLAYSTATUS_PLAYING_NON_DIEGETIC );
+#endif
+#endif
             }
             else
             {
+#ifdef FIX_550_FIRST_FRAME_ACCESS_ALT
+                hBinRendererTd->Sources[nS]->SrcSpatial_p->PosType = TDREND_POSTYPE_ABSOLUTE;
+#else
+#ifndef FIX_550_FIRST_FRAME_ACCESS
                 TDREND_MIX_SRC_SetPlayState( hBinRendererTd, nS, TDREND_PLAYSTATUS_PLAYING );
+#endif
+#endif
             }
             TDREND_MIX_SRC_SetDir( hBinRendererTd, nS, Dir );
         }
diff --git a/lib_rend/ivas_objectRenderer_hrFilt.c b/lib_rend/ivas_objectRenderer_hrFilt.c
index 0df5df6fcddb0adc706f14c542bedd0681efd3e8..8fb081da222f217a1e4d8fdd4853d46685757e78 100644
--- a/lib_rend/ivas_objectRenderer_hrFilt.c
+++ b/lib_rend/ivas_objectRenderer_hrFilt.c
@@ -79,7 +79,9 @@ ivas_error TDREND_REND_RenderSourceHRFilt(
     v_add( LeftOutputFrame, output_buf[0], output_buf[0], subframe_length );
     v_add( RightOutputFrame, output_buf[1], output_buf[1], subframe_length );
 
+#ifndef FIX_550_FIRST_FRAME_ACCESS
     Src_p->InputFrame_p += subframe_length; /* Increment input pointer */
+#endif
 
 
     return IVAS_ERR_OK;
diff --git a/lib_rend/ivas_objectRenderer_mix.c b/lib_rend/ivas_objectRenderer_mix.c
index 509d22d320f98ef6d1fcc17dc55b3ec8cc5ae14b..e2180023459a9ebcf77be8578f9cd711c3368dee 100644
--- a/lib_rend/ivas_objectRenderer_mix.c
+++ b/lib_rend/ivas_objectRenderer_mix.c
@@ -309,7 +309,11 @@ ivas_error TDREND_MIX_AddSrc(
     }
     else
     {
+#ifdef FIX_550_FIRST_FRAME_ACCESS_ALT
+        if ( ( PosType < TDREND_POSTYPE_ABSOLUTE ) || ( PosType > TDREND_POSTYPE_NON_DIEGETIC ) )
+#else
         if ( ( PosType < TDREND_POSTYPE_ABSOLUTE ) || ( PosType > TDREND_POSTYPE_RELATIVE_TO_LISTENER ) )
+#endif
         {
             return ( IVAS_ERROR( IVAS_ERR_INTERNAL, "Invalid position type!\n" ) );
         }
diff --git a/lib_rend/ivas_objectRenderer_sources.c b/lib_rend/ivas_objectRenderer_sources.c
index 8b4b910c5b1411874cd84b2af4e6a02b88912cfe..72fc1b4da460ef6dd332d28c299a78afbd7b0b46 100644
--- a/lib_rend/ivas_objectRenderer_sources.c
+++ b/lib_rend/ivas_objectRenderer_sources.c
@@ -218,7 +218,11 @@ static void TDREND_SRC_REND_Init(
 
     /* Internal state */
     SrcRend_p->InputAvailable = FALSE;
+#ifdef FIX_550_FIRST_FRAME_ACCESS_ALT
+    SrcRend_p->PlayStatus = TDREND_PLAYSTATUS_PLAYING;
+#else
     SrcRend_p->PlayStatus = TDREND_PLAYSTATUS_INITIAL;
+#endif
     /* SrcGain  */
     for ( nC = 0; nC < SPAT_BIN_MAX_INPUT_CHANNELS; nC++ )
     {
@@ -281,6 +285,7 @@ void TDREND_SRC_REND_UpdateFiltersFromSpatialParams(
     *filterlength = HrFiltSet_p->FiltLength;
 #endif
 
+#ifndef FIX_550_FIRST_FRAME_ACCESS_ALT
     /* 1. Map source pos to the coordinate system of the listener */
     switch ( SrcSpatial_p->PosType )
     {
@@ -300,6 +305,13 @@ void TDREND_SRC_REND_UpdateFiltersFromSpatialParams(
             TDREND_SPATIAL_VecMapToNewCoordSystem( SrcSpatial_p->Pos_p, Listener_p->Pos, Listener_p->Front, Listener_p->Up, Listener_p->Right, ListRelPos, ListRelPosAbs );
             break;
     }
+#else
+    if ( SrcSpatial_p->PosType == TDREND_POSTYPE_ABSOLUTE )
+    {
+
+        /* Absolute position */
+        TDREND_SPATIAL_VecMapToNewCoordSystem( SrcSpatial_p->Pos_p, Listener_p->Pos, Listener_p->Front, Listener_p->Up, Listener_p->Right, ListRelPos, ListRelPosAbs );
+#endif
 
     ListRelDist = TDREND_SPATIAL_VecNorm( ListRelPos );
 
@@ -319,7 +331,7 @@ void TDREND_SRC_REND_UpdateFiltersFromSpatialParams(
 #ifdef FIX_569_TD_FILTER_LENGTH
     GetFilterFromAngle( HrFiltSet_p, Elev, Azim, *filterlength, hrf_left, hrf_right, itd );
 #else
-    GetFilterFromAngle( HrFiltSet_p, Elev, Azim, hrf_left, hrf_right, itd );
+        GetFilterFromAngle( HrFiltSet_p, Elev, Azim, hrf_left, hrf_right, itd );
 #endif
 
     /* 6. Evaluate the directional and distance gains */
@@ -359,25 +371,40 @@ void TDREND_SRC_REND_UpdateFiltersFromSpatialParams(
 
     azim_delta = ( azim_delta > 180.0f ) ? ( azim_delta - 360 ) : ( ( azim_delta < -180.0f ) ? ( azim_delta + 360 ) : ( azim_delta ) ); /* map to -180:180 range */
     *intp_count = min( MAX_INTERPOLATION_STEPS, max( (int16_t) ( fabsf( azim_delta ) * MAX_ANGULAR_STEP_INV ), (int16_t) ( fabsf( elev_delta ) * MAX_ANGULAR_STEP_INV ) ) );
+#ifdef FIX_550_FIRST_FRAME_ACCESS_ALT
+}
+else /* TDREND_POSTYPE_NON_DIEGETIC */
+{
+    *itd = 0;
+    *Gain = 1.0f;
+    set_f( hrf_left, 0.0f, *filterlength );
+    set_f( hrf_right, 0.0f, *filterlength );
+    hrf_left[0] = ( SrcSpatial_p->Pos_p[1] + 1.f ) * 0.5f;
+    hrf_right[0] = 1.f - hrf_left[0];
+    *intp_count = MAX_INTERPOLATION_STEPS;
+    Src_p->elev_prev = 0;
+    Src_p->azim_prev = 360.0f; /* Dummy angle -- sets max interpolation if switching to TDREND_POSTYPE_ABSOLUTE */
+}
+#endif
 
-    if ( ( *intp_count > 0 ) && subframe_update_flag )
-    {
-        /* Set deltas for interpolation */
-        v_sub( hrf_left, hrf_left_prev, hrf_left_delta, *filterlength );
-        v_multc( hrf_left_delta, 1.0f / *intp_count, hrf_left_delta, *filterlength );
-        v_sub( hrf_right, hrf_right_prev, hrf_right_delta, *filterlength );
-        v_multc( hrf_right_delta, 1.0f / *intp_count, hrf_right_delta, *filterlength );
-    }
-    else
-    {
-        /* No interpolation, just set the new filters and reset deltas */
-        mvr2r( hrf_left, hrf_left_prev, *filterlength );
-        mvr2r( hrf_right, hrf_right_prev, *filterlength );
-        set_f( hrf_left_delta, 0.0f, *filterlength );
-        set_f( hrf_right_delta, 0.0f, *filterlength );
-    }
+if ( ( *intp_count > 0 ) && subframe_update_flag )
+{
+    /* Set deltas for interpolation */
+    v_sub( hrf_left, hrf_left_prev, hrf_left_delta, *filterlength );
+    v_multc( hrf_left_delta, 1.0f / *intp_count, hrf_left_delta, *filterlength );
+    v_sub( hrf_right, hrf_right_prev, hrf_right_delta, *filterlength );
+    v_multc( hrf_right_delta, 1.0f / *intp_count, hrf_right_delta, *filterlength );
+}
+else
+{
+    /* No interpolation, just set the new filters and reset deltas */
+    mvr2r( hrf_left, hrf_left_prev, *filterlength );
+    mvr2r( hrf_right, hrf_right_prev, *filterlength );
+    set_f( hrf_left_delta, 0.0f, *filterlength );
+    set_f( hrf_right_delta, 0.0f, *filterlength );
+}
 
-    return;
+return;
 }
 
 
@@ -682,7 +709,11 @@ void TDREND_SRC_Init(
     /* Reset memory buffers */
     Src_p->itd = 0;
     Src_p->previtd = 0;
-    Src_p->filterlength = -1;
+#ifdef FIX_550_FIRST_FRAME_ACCESS
+    Src_p->filterlength = 1; /* Init to unit impulse of length 1 */
+#else
+        Src_p->filterlength = -1;
+#endif
     set_f( Src_p->mem_itd, 0.0f, ITD_MEM_LEN );
     set_f( Src_p->mem_hrf_left, 0.0f, SFX_SPAT_BIN_MAX_FILTER_LENGTH - 1 );
     set_f( Src_p->mem_hrf_right, 0.0f, SFX_SPAT_BIN_MAX_FILTER_LENGTH - 1 );
@@ -693,6 +724,9 @@ void TDREND_SRC_Init(
     Src_p->hrf_right_prev[0] = 1;
     Src_p->azim_prev = 0.0f;
     Src_p->elev_prev = 0.0f;
+#ifdef FIX_550_FIRST_FRAME_ACCESS
+    Src_p->Gain = 1;
+#endif
     Src_p->prevGain = 1.0f;
 
     return;