diff --git a/lib_dec/ivas_stat_dec.h b/lib_dec/ivas_stat_dec.h
index e63f6c3e43b9cbb38d0dad857509c47040c9132d..415734d1b64fdd90e422989321fef9b54ea02ec1 100644
--- a/lib_dec/ivas_stat_dec.h
+++ b/lib_dec/ivas_stat_dec.h
@@ -800,10 +800,11 @@ typedef struct ivas_mc_paramupmix_dec_data_structure
     float beta_prev[MC_PARAMUPMIX_COMBINATIONS][IVAS_MAX_NUM_BANDS];
     int32_t alpha_quant[MC_PARAMUPMIX_COMBINATIONS][IVAS_MAX_NUM_BANDS];
     int32_t beta_quant[MC_PARAMUPMIX_COMBINATIONS][IVAS_MAX_NUM_BANDS];
-    bool first_frame;
+    int16_t first_frame;
     float *pcm_delay[MC_PARAMUPMIX_MAX_TRANSPORT_CHANS];
 
 } MC_PARAMUPMIX_DEC_DATA, *MC_PARAMUPMIX_DEC_HANDLE;
+
 /*------------------------------------------------------------------------------------------*
  * SPAR decoder structures
  *------------------------------------------------------------------------------------------*/
diff --git a/lib_enc/ivas_stat_enc.h b/lib_enc/ivas_stat_enc.h
index 4f2f375af7094af2561f6b387a47f98565b070ef..4e1f37d27df2e3530ce3b2fe847ffaf1bd02e637 100644
--- a/lib_enc/ivas_stat_enc.h
+++ b/lib_enc/ivas_stat_enc.h
@@ -736,6 +736,7 @@ typedef struct ivas_param_mc_enc_data_structure
 /*----------------------------------------------------------------------------------*
  * MC ParamUpmix Mode encoder structures
  *----------------------------------------------------------------------------------*/
+
 typedef struct ivas_mc_paramupmix_enc_data_structure
 {
     ivas_trans_det_state_t *hTranDet[MC_PARAMUPMIX_COMBINATIONS * MC_PARAMUPMIX_NCH];
@@ -746,7 +747,8 @@ typedef struct ivas_mc_paramupmix_enc_data_structure
     float *midside[MC_PARAMUPMIX_COMBINATIONS][MC_PARAMUPMIX_NCH]; /* hold PCM of mid-side data */
     int32_t alpha_quant_prev[MC_PARAMUPMIX_COMBINATIONS][IVAS_MAX_NUM_BANDS];
     int32_t beta_quant_prev[MC_PARAMUPMIX_COMBINATIONS][IVAS_MAX_NUM_BANDS];
-    bool first_frame;
+    int16_t first_frame;
+
 } MC_PARAMUPMIX_ENC_DATA, *MC_PARAMUPMIX_ENC_HANDLE;
 
 /*----------------------------------------------------------------------------------*