diff --git a/laser_control/protocol.py b/laser_control/protocol.py
index 262826a..9b1e6cc 100644
--- a/laser_control/protocol.py
+++ b/laser_control/protocol.py
@@ -404,12 +404,12 @@ class Protocol:
         def get_int_word(num: int) -> int:
             return int(get_word(num), 16)
 
-        # CRC check: XOR over words 1..13, compare with word 14
+        # CRC check: XOR over words 1..13 (wire order), compare with word 14 (wire order)
         crc_words = [hex_str[i:i+4] for i in range(4, len(hex_str)-4, 4)]
         computed = int(crc_words[0], 16)
         for w in crc_words[1:]:
             computed ^= int(w, 16)
-        stored = get_int_word(14)
+        stored = int(hex_str[56:60], 16)
         if computed != stored:
             raise CRCError(expected=computed, received=stored)
 
diff --git a/tests/conftest.py b/tests/conftest.py
index 2527de3..6160309 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -76,8 +76,8 @@ def make_valid_response(
     for w in crc_words[1:]:
         crc_val ^= int(w, 16)
 
-    # Replace CRC word
-    hex_str = hex_str[:56] + _flipfour(_int_to_hex4(crc_val))
+    # Replace CRC word (stored in wire order, no flipfour)
+    hex_str = hex_str[:56] + _int_to_hex4(crc_val)
     return bytes.fromhex(hex_str)