diff --git a/src_base/xeve_eco.c b/src_base/xeve_eco.c
index 36b89fd..fee3ef7 100644
--- a/src_base/xeve_eco.c
+++ b/src_base/xeve_eco.c
@@ -202,6 +202,7 @@ int xeve_eco_sps(XEVE_BSW *bs, XEVE_SPS *sps)
     }
 
     u32 t0 = 0;
+    xeve_bsw_write1(bs, 1);
     while(!XEVE_BSW_IS_BYTE_ALIGN(bs)) {
         xeve_bsw_write1(bs, t0);
     }
@@ -235,6 +236,7 @@ int xeve_eco_pps(XEVE_BSW *bs, XEVE_SPS *sps, XEVE_PPS *pps)
         xeve_bsw_write_ue(bs, pps->cu_qp_delta_area - 6);
     }
     u32 t0 = 0;
+    xeve_bsw_write1(bs, 1);
     while(!XEVE_BSW_IS_BYTE_ALIGN(bs)) {
         xeve_bsw_write1(bs, t0);
     }
@@ -331,7 +333,7 @@ static void write_sei_userdata_unregistered(XEVE_SEI_PAYLOAD *sei_userdata, XEVE
         xeve_bsw_write(bs, 0xff, 8);
     xeve_bsw_write(bs, payload_type, 8);
 
-    u32 payload_size = (ISO_IEC_11578_LEN + sei_userdata->payload_size) << 3;
+    u32 payload_size = ISO_IEC_11578_LEN + sei_userdata->payload_size;
     for(; payload_size >= 0xff; payload_size -= 0xff)
         xeve_bsw_write(bs, 0xff, 8);
     xeve_bsw_write(bs, payload_size, 8);
@@ -368,6 +370,7 @@ int xeve_eco_emitsei(XEVE_CTX *ctx, XEVE_BSW *bs)
         write_sei_userdata_unregistered(&sei_userdata_unregistered, bs);
     }
 
+    xeve_bsw_write1(bs, 1);
     while(!XEVE_BSW_IS_BYTE_ALIGN(bs)) {
         xeve_bsw_write1(bs, 0);
     }
@@ -382,6 +385,7 @@ int xeve_eco_sei(XEVE_CTX *ctx, XEVE_BSW *bs)
         xeve_eco_signature(ctx, bs);
     }
 
+    xeve_bsw_write1(bs, 1);
     while(!XEVE_BSW_IS_BYTE_ALIGN(bs)) {
         xeve_bsw_write1(bs, 0);
     }
diff --git a/src_main/xevem_eco.c b/src_main/xevem_eco.c
index 228c0de..eccf2c4 100644
--- a/src_main/xevem_eco.c
+++ b/src_main/xevem_eco.c
@@ -263,6 +263,7 @@ int xevem_eco_aps_gen(XEVE_BSW *bs, XEVE_APS_GEN *aps, int bit_depth)
     assert(aps_extension_flag == 0);
 
     u32 t0 = 0;
+    xeve_bsw_write1(bs, 1);
     while(!XEVE_BSW_IS_BYTE_ALIGN(bs)) {
         xeve_bsw_write1(bs, t0);
     }
@@ -423,6 +424,7 @@ int xevem_eco_sps(XEVE_BSW *bs, XEVE_SPS *sps)
     }
 
     u32 t0 = 0;
+    xeve_bsw_write1(bs, 1);
     while(!XEVE_BSW_IS_BYTE_ALIGN(bs)) {
         xeve_bsw_write1(bs, t0);
     }
@@ -486,6 +488,7 @@ int xevem_eco_pps(XEVE_BSW *bs, XEVE_SPS *sps, XEVE_PPS *pps)
         xeve_bsw_write_ue(bs, pps->cu_qp_delta_area - 6);
     }
     u32 t0 = 0;
+    xeve_bsw_write1(bs, 1);
     while(!XEVE_BSW_IS_BYTE_ALIGN(bs)) {
         xeve_bsw_write1(bs, t0);
     }