diff --git a/lib_com/options.h b/lib_com/options.h
index ba42ad211feac9a9bfc48977882e5bf6be87049f..0f3cd8cbeee7ac8d4341fbb5ebb8a299330d39bf 100755
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -197,7 +197,7 @@
 #define FIX_615_UBSAN_SPAR_TO_DIRAC                     /*Dlb : Fix for UBSAN issue 615*/
 #define FIX_626_VARIABLE_TYPE_MDCT_CONC                 /* FhG: trivial fix to fix USAN error */
 #define FIX_616_DIV_ZERO_MCT                            /*FhG : Fix UBSAN division by zero error of issue 616*/
-
+#define FIX_279_CODE_COVERAGE                           /*Dlb : issue 279 , clean up unused function*/
 /* ################## End BE DEVELOPMENT switches ######################### */
 
 
diff --git a/lib_dec/ivas_qmetadata_dec.c b/lib_dec/ivas_qmetadata_dec.c
index e4c69cd288a01bdc124ae7e289fe2befc6eb75b0..453e27b320d6e7fce444c7dd9068f51a0f959eb6 100644
--- a/lib_dec/ivas_qmetadata_dec.c
+++ b/lib_dec/ivas_qmetadata_dec.c
@@ -1455,7 +1455,7 @@ int16_t ivas_qmetadata_dec_sid_decode(
             }
         }
     }
-    /* TODO: temporary hack to keep BE */
+
     if ( ivas_format != SBA_FORMAT )
     {
         metadata_sid_bits = ( IVAS_SID_5k2 - SID_2k40 ) / FRAMES_PER_SEC - SID_FORMAT_NBITS;
diff --git a/lib_dec/ivas_spar_md_dec.c b/lib_dec/ivas_spar_md_dec.c
index c61effd67359f2e1873e7230e1ddda0e154b4b38..ec363399e417f67e34c6dbd4ac969b04317976ed 100644
--- a/lib_dec/ivas_spar_md_dec.c
+++ b/lib_dec/ivas_spar_md_dec.c
@@ -72,15 +72,20 @@ static void ivas_decode_huffman_bs( ivas_spar_md_dec_state_t *hMdDec, Decoder_St
 static void ivas_fill_band_coeffs_idx( ivas_band_coeffs_ind_t *pBands_idx, const int16_t nB, int16_t *pSymbol_re, ivas_cell_dim_t *pCell_dims, ivas_coeffs_type_t coeff_type, const int16_t planarCP );
 
 #else
+#ifndef FIX_279_CODE_COVERAGE
 static void ivas_decode_arith_bs( ivas_spar_md_dec_state_t *hMdDec, Decoder_State *st, const uint16_t qsi, const int16_t nB, const int16_t bands_bw, int16_t *pDo_diff, const int16_t freq_diff, const int16_t strat, const int32_t ivas_total_brate );
+#else
+static void ivas_decode_arith_bs( ivas_spar_md_dec_state_t *hMdDec, Decoder_State *st, const uint16_t qsi, const int16_t nB, const int16_t bands_bw, int16_t *pDo_diff, const int16_t strat, const int32_t ivas_total_brate );
 
+#endif
 static void ivas_decode_huffman_bs( ivas_spar_md_dec_state_t *hMdDec, Decoder_State *st, const uint16_t qsi, const int16_t nB, const int16_t bands_bw );
 
 static void ivas_fill_band_coeffs_idx( ivas_band_coeffs_ind_t *pBands_idx, const int16_t nB, int16_t *pSymbol_re, ivas_cell_dim_t *pCell_dims, ivas_coeffs_type_t coeff_type );
 
 #endif
+#ifndef FIX_279_CODE_COVERAGE
 static void ivas_get_band_idx_from_differential( ivas_spar_md_t *pSpar_md, const int16_t q_levels[2], const int16_t one_sided, const int16_t nB, const ivas_coeffs_type_t coeff_type );
-
+#endif
 static void ivas_mat_col_rearrange( float in_re[IVAS_SPAR_MAX_CH][IVAS_SPAR_MAX_CH], const int16_t order[IVAS_SPAR_MAX_CH], const int16_t i_ts, float ***mixer_mat, const int16_t bands, const int16_t num_ch );
 
 static void ivas_spar_dec_compute_ramp_down_post_matrix( ivas_spar_md_dec_state_t *hMdDec, const int16_t num_bands, const int16_t bfi, const int16_t num_md_sub_frames );
@@ -1799,7 +1804,11 @@ static void ivas_spar_dec_parse_md_bs(
     int16_t ii, jj, ndec, ndm, b, idx;
     uint16_t qsi;
     ivas_quant_strat_t qs;
+#ifndef FIX_279_CODE_COVERAGE
     int16_t strat, freq_diff, no_ec;
+#else
+    int16_t strat, no_ec;
+#endif
     int16_t do_diff[IVAS_MAX_NUM_BANDS];
 #ifndef FIX_280_PLANAR_CP
     int16_t planarCP;
@@ -1931,7 +1940,9 @@ static void ivas_spar_dec_parse_md_bs(
 #ifdef SPAR_HOA_DBG
     /*fprintf(stdout, "\n\n no_ec = %d, strat = %d\n", no_ec, strat);*/
 #endif
+#ifndef FIX_279_CODE_COVERAGE
     freq_diff = 0;
+#endif
     no_ec = 0;
 
     if ( strat < 2 )
@@ -1986,7 +1997,10 @@ static void ivas_spar_dec_parse_md_bs(
 
     if ( no_ec == 0 )
     {
-        ivas_decode_arith_bs( hMdDec, st0, qsi, *nB, *bands_bw, do_diff, freq_diff,
+        ivas_decode_arith_bs( hMdDec, st0, qsi, *nB, *bands_bw, do_diff,
+#ifndef FIX_279_CODE_COVERAGE
+                              freq_diff,
+#endif
 #ifndef FIX_280_PLANAR_CP
                               planarCP,
 #endif
@@ -2141,7 +2155,9 @@ static void ivas_decode_arith_bs(
     const int16_t nB,
     const int16_t bands_bw,
     int16_t *pDo_diff,
+#ifndef FIX_279_CODE_COVERAGE
     const int16_t freq_diff,
+#endif
 #ifndef FIX_280_PLANAR_CP
     const int16_t planarCP,
 #endif
@@ -2331,7 +2347,7 @@ static void ivas_decode_arith_bs(
                                planarCP
 #endif
     );
-
+#ifndef FIX_279_CODE_COVERAGE
     if ( freq_diff == 1 )
     {
 #ifdef SPAR_HOA_DBG
@@ -2342,11 +2358,11 @@ static void ivas_decode_arith_bs(
         ivas_get_band_idx_from_differential( &hMdDec->spar_md, hMdDec->spar_md_cfg.quant_strat->P_r.q_levels, 1, nB, DECD_COEFF );
         ivas_get_band_idx_from_differential( &hMdDec->spar_md, hMdDec->spar_md_cfg.quant_strat->P_c.q_levels, 0, nB, DECX_COEFF );
     }
-
+#endif
     return;
 }
 
-
+#ifndef FIX_279_CODE_COVERAGE
 /*-----------------------------------------------------------------------------------------*
  * Function ivas_get_band_idx_from_differential()
  *
@@ -2430,7 +2446,7 @@ static void ivas_get_band_idx_from_differential(
     return;
 }
 
-
+#endif
 /*-----------------------------------------------------------------------------------------*
  * Function ivas_fill_band_coeffs_idx()
  *
diff --git a/lib_enc/ivas_qmetadata_enc.c b/lib_enc/ivas_qmetadata_enc.c
index 7cf68d677dd3939231d2cd2680cc1bde6285eaa7..591b37fdbbc7f64103644654813ee057fb84f04b 100644
--- a/lib_enc/ivas_qmetadata_enc.c
+++ b/lib_enc/ivas_qmetadata_enc.c
@@ -988,7 +988,7 @@ void ivas_qmetadata_enc_sid_encode(
     else
     {
 #ifdef FIX_QMETA_SID_5k2
-        /* TODO: still use old sid frame size to keep bitexactness */
+
         metadata_sid_bits = ( IVAS_SID_5k2 - SID_2k40 ) / FRAMES_PER_SEC - SID_FORMAT_NBITS;
 #else
         metadata_sid_bits = ( 4400 /*IVAS_SID_5k2*/ - SID_2k40 ) / FRAMES_PER_SEC - SID_FORMAT_NBITS;
@@ -1231,7 +1231,6 @@ void ivas_qmetadata_enc_sid_encode(
     }
 #endif
 
-    /* TODO: temporary to keep BE */
     if ( ivas_format != SBA_FORMAT )
     {
         metadata_sid_bits = ( IVAS_SID_5k2 - SID_2k40 ) / FRAMES_PER_SEC - SID_FORMAT_NBITS;