diff --git a/cram/cram_codecs.c b/cram/cram_codecs.c
index a72419e1c..fe454f794 100644
--- a/cram/cram_codecs.c
+++ b/cram/cram_codecs.c
@@ -3613,7 +3613,10 @@ int cram_byte_array_stop_decode_block(cram_slice *slice, cram_codec *c,
     cp = b->data + b->idx;
     cp_end = b->data + b->uncomp_size;
 
-    stop = c->u.byte_array_stop.stop;
+    // STOP byte is hard-coded as zero by our name tokeniser decoder
+    // implementation, so we may ignore what was requested.
+    stop = b->orig_method == TOK3 ? 0 : c->u.byte_array_stop.stop;
+
     if (cp_end - cp < out->alloc - out->byte) {
         unsigned char *out_cp = BLOCK_END(out);
         while (cp != cp_end && *cp != stop)
diff --git a/cram/cram_io.c b/cram/cram_io.c
index 35dbb99c8..5e5891114 100644
--- a/cram/cram_io.c
+++ b/cram/cram_io.c
@@ -1698,8 +1698,7 @@ int cram_uncompress_block(cram_block *b) {
             free(uncomp);
             return -1;
         }
-        b->orig_method = RANS_PR0 + (b->data[0]&1)
-            + 2*((b->data[0]&0x40)>0) + 4*((b->data[0]&0x80)>0);
+        b->orig_method = RANSPR;
         free(b->data);
         b->data = (unsigned char *)uncomp;
         b->alloc = usize2;
@@ -1718,8 +1717,7 @@ int cram_uncompress_block(cram_block *b) {
             free(uncomp);
             return -1;
         }
-        b->orig_method = ARITH_PR0 + (b->data[0]&1)
-            + 2*((b->data[0]&0x40)>0) + 4*((b->data[0]&0x80)>0);
+        b->orig_method = ARITH;
         free(b->data);
         b->data = (unsigned char *)uncomp;
         b->alloc = usize2;