diff --git a/lib_com/options.h b/lib_com/options.h
index 95acf097772968d9db2d5c1370fd8a2c1f04cb70..85f66980645f827b57a0cd503522b7aecb49098d 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -97,6 +97,7 @@
 
 #define FIX_BASOP_2451_HQ_FEC_SELECTOR                  /* Eri: Resolve basop issue 2451, wrong condition on env_stab_plc_fx */
 #define FIX_2398_PRECISSION_ORIENTATION_TRACKING        /* FhG: use refinement of Sqrt32 within certain functions*/
+#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" */
 
 
 /* ##################### End NON-BE switches ########################### */
diff --git a/lib_enc/acelp_core_enc_fx.c b/lib_enc/acelp_core_enc_fx.c
index 904577880ae89eb23a6d403c0f9ac050d9b66a1e..b74c92599ae39d8e3e451e135e7d1028e21bfae3 100644
--- a/lib_enc/acelp_core_enc_fx.c
+++ b/lib_enc/acelp_core_enc_fx.c
@@ -553,6 +553,10 @@ ivas_error acelp_core_enc_fx(
         move16();
         uc_two_stage_flag = 0;
         move16();
+#ifdef FIX_1543_MID_LSF_BITS
+        st->acelp_cfg.mid_lsf_bits = -1;
+        move16();
+#endif
 
         test();
         IF( !nelp_mode && !ppp_mode )