diff --git a/lib_com/options.h b/lib_com/options.h
index 00fd028cf58629320fce47e3ed1d27862a484104..2d3b49c9e6c21911816f967827808832c4616ac0 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -116,7 +116,7 @@
 #define FIX_2320_OOB_SCE_SWITCHING                      /* VA: basop issue 2320: Correct the length of the buffer to be scaled in SCE/CPE switching */
 #define FIX_2302_LSF_CDBK_THRESHOLD                     /* VA: basop issue 2302: fix threshold for LSF Q codebook-type decision  */
 #define FIX_1500_ISM_MD_DTX                             /* VA: float issue 1500: fix ISM elevation metadata smoothing in DTX */
-
+#define FIX_2366_PRECISION_WSP                          /* VA: basop issue 2366: address lost of precision in old_wsp */                                                        
 /* ##################### End NON-BE switches ########################### */
 
 
diff --git a/lib_enc/ivas_cpe_enc_fx.c b/lib_enc/ivas_cpe_enc_fx.c
index 6e7455d638a3ce3a16aef14950e5274e80ce177c..e9ca1314bcc72dac69fac923665f8f3aa54117b8 100644
--- a/lib_enc/ivas_cpe_enc_fx.c
+++ b/lib_enc/ivas_cpe_enc_fx.c
@@ -1273,13 +1273,14 @@ ivas_error ivas_cpe_enc_fx(
     /*----------------------------------------------------------------*
      * Core Encoder
      *----------------------------------------------------------------*/
-
+#ifndef FIX_2366_PRECISION_WSP
     FOR( n = 0; n < n_CoreChannels; n++ )
     {
         Scale_sig( old_wsp_fx[n], L_WSP, sub( e_old_wsp[n], Q16 ) ); /* exp(16) */
         e_old_wsp[n] = 16;
         move16();
     }
+#endif
     IF( NE_32( ( error = ivas_core_enc_fx( NULL, hCPE, st_ivas->hMCT, n_CoreChannels, old_inp_12k8_16fx, old_inp_16k_16fx, Q_new, ener_fx, A_fx, Aw_fx, epsP_fx, epsP_fx_q, lsp_new_fx, lsp_mid_fx, vad_hover_flag, attack_flag, realBuffer_fx, imagBuffer_fx, q_re_im_buf, old_wsp_fx, e_old_wsp, loc_harm, cor_map_sum_fx, vad_flag_dtx, enerBuffer_fx, enerBuffer_fx_exp, fft_buff_fx, tdm_SM_or_LRTD_Pri, ivas_format, 0 ) ), IVAS_ERR_OK ) )
     {
         return error;
diff --git a/lib_enc/ivas_ism_enc_fx.c b/lib_enc/ivas_ism_enc_fx.c
index 40f683925285942b8a23d87b066c23d35a838a37..d0d66e1d4ab2103ccc233fae700b3e275a312d14 100644
--- a/lib_enc/ivas_ism_enc_fx.c
+++ b/lib_enc/ivas_ism_enc_fx.c
@@ -459,9 +459,11 @@ ivas_error ivas_ism_enc_fx(
         test();
         IF( !dtx_flag || ( dtx_flag && EQ_16( sce_id, st_ivas->hISMDTX->sce_id_dtx ) ) )
         {
+#ifndef FIX_2366_PRECISION_WSP
             Scale_sig( old_wsp_fx[sce_id][0], L_WSP, sub( e_old_wsp[sce_id][0], Q16 ) ); /* exp(16) */
             e_old_wsp[sce_id][0] = 16;
             move16();
+#endif
             IF( NE_32( ( error = ivas_core_enc_fx( hSCE, NULL, NULL, 1, old_inp_12k8_fx[sce_id], old_inp_16k_fx[sce_id], Q_new[sce_id], ener_fx[sce_id], A_fx[sce_id], Aw_fx[sce_id], epsP_fx[sce_id], epsP_fx_q[sce_id], lsp_new_fx[sce_id], lsp_mid_fx[sce_id], vad_hover_flag[sce_id], attack_flag[sce_id], realBuffer_fx[sce_id], imagBuffer_fx[sce_id], &q_re_im_buf[sce_id], old_wsp_fx[sce_id], e_old_wsp[sce_id], loc_harm[sce_id], cor_map_sum_fx[sce_id], vad_flag_dtx[sce_id], enerBuffer_fx[sce_id], enerBuffer_fx_exp[sce_id], fft_buff_fx[sce_id], 0, ISM_FORMAT, 0 ) ), IVAS_ERR_OK ) )
             {
                 return error;
diff --git a/lib_enc/ivas_sce_enc_fx.c b/lib_enc/ivas_sce_enc_fx.c
index 4d639c961ca13c7ce256ecd3481d68b59c778e90..277c2afddb23938c3a5c4b1f89dbe480770bdda5 100644
--- a/lib_enc/ivas_sce_enc_fx.c
+++ b/lib_enc/ivas_sce_enc_fx.c
@@ -372,10 +372,11 @@ ivas_error ivas_sce_enc_fx(
     /*----------------------------------------------------------------*
      * Encoder
      *----------------------------------------------------------------*/
-
+#ifndef FIX_2366_PRECISION_WSP
     Scale_sig( old_wsp_fx[0], L_WSP, sub( e_old_wsp[0], Q16 ) ); // Q(15-16)
     e_old_wsp[0] = 16;
     move16();
+#endif
     IF( NE_32( ( error = ivas_core_enc_fx( hSCE, NULL, NULL, 1, old_inp_12k8_fx, old_inp_16k_fx, Q_new, ener_fx, A_fx, Aw_fx, epsP_fx, epsP_fx_q, lsp_new_fx, lsp_mid_fx, vad_hover_flag, attack_flag, realBuffer_fx, imagBuffer_fx, &q_re_im_buf, old_wsp_fx, e_old_wsp, loc_harm, cor_map_sum_fx, vad_flag_dtx, enerBuffer_fx, enerBuffer_fx_exp, fft_buff_fx, 0, ivas_format, flag_16k_smc ) ), IVAS_ERR_OK ) )
     {
         return error;