diff --git a/minimateplus/framing.py b/minimateplus/framing.py
index 4f0949c..a7ad295 100644
--- a/minimateplus/framing.py
+++ b/minimateplus/framing.py
@@ -112,10 +112,13 @@ def build_5a_frame(offset_word: int, raw_params: bytes) -> bytes:
 
     Args:
         offset_word: 16-bit offset (0x1004 for probe/chunks, 0x005A for term).
-        raw_params:  10 params bytes (from bulk_waveform_params or
-                     bulk_waveform_term_params). 0x10 bytes in params ARE
-                     DLE-stuffed (BW confirmed this for counter=0x1000 and
-                     counter=0x1004 in the capture).
+        raw_params:  10 or 11 params bytes (from bulk_waveform_params or
+                     bulk_waveform_term_params). 0x10 bytes in params are
+                     written RAW — NOT DLE-stuffed. Confirmed 2026-04-06 by
+                     comparing wire bytes: BW sends bare `10 04` for chunk 1
+                     (counter=0x1004), not stuffed `10 10 04`. Device reads
+                     params at fixed byte positions; stuffing shifts the bytes
+                     and corrupts the counter, causing device to ignore the frame.
 
     Returns:
         Complete frame bytes: [ACK][STX][stuffed_section][chk][ETX]
@@ -131,9 +134,7 @@ def build_5a_frame(offset_word: int, raw_params: bytes) -> bytes:
     s += b"\x00"                                 # field3
     s += bytes([(offset_word >> 8) & 0xFF,       # offset_hi — raw, NOT stuffed
                  offset_word & 0xFF])            # offset_lo
-    for b in raw_params:                         # params — DLE-stuffed
-        if b == DLE:
-            s.append(DLE)
+    for b in raw_params:                         # params — NOT DLE-stuffed (raw bytes, match BW wire format)
         s.append(b)
 
     # DLE-aware checksum: for 0x10 XX pairs count XX; for lone bytes count them