diff --git a/clash-cores/src/Clash/Cores/Sgmii/BitSlip.hs b/clash-cores/src/Clash/Cores/Sgmii/BitSlip.hs
index 5ff78dcbd7..36f4a5cd87 100644
--- a/clash-cores/src/Clash/Cores/Sgmii/BitSlip.hs
+++ b/clash-cores/src/Clash/Cores/Sgmii/BitSlip.hs
@@ -56,7 +56,7 @@ bitSlipT BSFail{..} (cg, _)
   | ns == repeat (fromJust n) = BSOk s (fromJust n) 0
   | otherwise = BSFail s ns hist
  where
-  s = resize $ _s ++# cg
+  s = resize $ _s ++# (v2bv . reverse . bv2v) cg
   ns = maybe _ns (_ns <<+) n
   hist = map pack $ take d10 $ windows1d d7 $ bv2v s
 
@@ -67,7 +67,7 @@ bitSlipT BSOk{..} (cg, syncStatus)
   | failTimer >= timeout (Proxy @dom) = BSFail s (repeat 0) (repeat 0)
   | otherwise = BSOk s _n failTimer
  where
-  s = resize $ _s ++# cg
+  s = resize $ _s ++# (v2bv . reverse . bv2v) cg
   failTimer = if syncStatus == Fail then _failTimer + 1 else 0
 
 -- | Output function for 'bitSlip' that takes the calculated index value and
@@ -80,10 +80,10 @@ bitSlipO ::
   (BitSlipState dom, BitVector 10, Bool)
 bitSlipO self@BSFail{..} = (self, o, False)
  where
-  o = resize $ rotateR _s 10
+  o = (v2bv . reverse . bv2v) $ resize $ rotateR _s 10
 bitSlipO self@BSOk{..} = (self, o, True)
  where
-  o = resize $ rotateR _s (13 - fromEnum _n)
+  o = (v2bv . reverse . bv2v) $ resize $ rotateR _s (10 - fromEnum _n)
 
 -- | Function that takes a code word and returns the same code word, but if a
 --   comma is detected the code words is shifted such that the comma is at the