diff --git a/X10D/src/IO/DoubleExtensions.cs b/X10D/src/IO/DoubleExtensions.cs
index 728cada44..c42a7ef53 100644
--- a/X10D/src/IO/DoubleExtensions.cs
+++ b/X10D/src/IO/DoubleExtensions.cs
@@ -48,11 +48,11 @@ public static bool TryWriteBigEndian(this double value, Span<byte> destination)
 #else
         if (BitConverter.IsLittleEndian)
         {
-            return MemoryMarshal.TryWrite(destination, ref value);
+            long tmp = BinaryPrimitives.ReverseEndianness(BitConverter.DoubleToInt64Bits(value));
+            return MemoryMarshal.TryWrite(destination, ref tmp);
         }
 
-        long tmp = BinaryPrimitives.ReverseEndianness(BitConverter.DoubleToInt64Bits(value));
-        return MemoryMarshal.TryWrite(destination, ref tmp);
+        return MemoryMarshal.TryWrite(destination, ref value);
 #endif
     }
 
@@ -67,7 +67,7 @@ public static bool TryWriteLittleEndian(this double value, Span<byte> destinatio
 #if NET5_0_OR_GREATER
         return BinaryPrimitives.TryWriteDoubleLittleEndian(destination, value);
 #else
-        if (!BitConverter.IsLittleEndian)
+        if (BitConverter.IsLittleEndian)
         {
             return MemoryMarshal.TryWrite(destination, ref value);
         }
diff --git a/X10D/src/IO/SingleExtensions.cs b/X10D/src/IO/SingleExtensions.cs
index d7992612e..539e919b3 100644
--- a/X10D/src/IO/SingleExtensions.cs
+++ b/X10D/src/IO/SingleExtensions.cs
@@ -50,11 +50,11 @@ public static bool TryWriteBigEndian(this float value, Span<byte> destination)
 #else
         if (BitConverter.IsLittleEndian)
         {
-            return MemoryMarshal.TryWrite(destination, ref value);
+            int tmp = BinaryPrimitives.ReverseEndianness(BitConverter.SingleToInt32Bits(value));
+            return MemoryMarshal.TryWrite(destination, ref tmp);
         }
 
-        int tmp = BinaryPrimitives.ReverseEndianness(BitConverter.SingleToInt32Bits(value));
-        return MemoryMarshal.TryWrite(destination, ref tmp);
+        return MemoryMarshal.TryWrite(destination, ref value);
 #endif
     }
 
@@ -69,7 +69,7 @@ public static bool TryWriteLittleEndian(this float value, Span<byte> destination
 #if NET5_0_OR_GREATER
         return BinaryPrimitives.TryWriteSingleLittleEndian(destination, value);
 #else
-        if (!BitConverter.IsLittleEndian)
+        if (BitConverter.IsLittleEndian)
         {
             return MemoryMarshal.TryWrite(destination, ref value);
         }