diff --git a/src/biquad_filter.jl b/src/biquad_filter.jl
index ea77750..a66bbb5 100644
--- a/src/biquad_filter.jl
+++ b/src/biquad_filter.jl
@@ -83,7 +83,8 @@ end
     end
 
     # fix start value
-    Y[1] = Y[2]
+    Y[1] = Y[3]
+    Y[2] = Y[3]
     
     Y
 end