diff --git a/Capnp.Net.Runtime.Tests/TcpRpcInterop.cs b/Capnp.Net.Runtime.Tests/TcpRpcInterop.cs
index e7403cb..a83f2ae 100644
--- a/Capnp.Net.Runtime.Tests/TcpRpcInterop.cs
+++ b/Capnp.Net.Runtime.Tests/TcpRpcInterop.cs
@@ -259,7 +259,7 @@ namespace Capnp.Net.Runtime.Tests
             }
         }
 
-        [TestMethod, Timeout(10000)]
+        [TestMethod, Timeout(20000)]
         public void ReleaseOnCancelClient()
         {
             // Since we have a threaded model, there is no way to deterministically provoke the situation
@@ -774,7 +774,9 @@ namespace Capnp.Net.Runtime.Tests
 
                         var cap = new TestCallOrderImpl();
                         cap.CountToDispose = 6;
+#if DEBUG_DISPOSE
                         Skeleton.BeginAssertNotDisposed(cap);
+#endif
                         var earlyCall = main.GetCallSequence(0, default);
 
                         var echo = main.Echo(cap, default);
@@ -809,7 +811,9 @@ namespace Capnp.Net.Runtime.Tests
                                 Assert.AreEqual(4u, call4.Result);
                                 Assert.AreEqual(5u, call5.Result);
 
+#if DEBUG_DISPOSE
                                 Skeleton.EndAssertNotDisposed(cap);
+#endif
                             }
                         }
                     }
diff --git a/Capnp.Net.Runtime/Rpc/RpcEngine.cs b/Capnp.Net.Runtime/Rpc/RpcEngine.cs
index cb20bf6..be864fe 100644
--- a/Capnp.Net.Runtime/Rpc/RpcEngine.cs
+++ b/Capnp.Net.Runtime/Rpc/RpcEngine.cs
@@ -234,11 +234,11 @@ namespace Capnp.Rpc
 
             PendingQuestion AllocateQuestion(ConsumedCapability target, SerializerState inParams)
             {
-                uint questionId = RandId();
-                var question = new PendingQuestion(this, questionId, target, inParams);
-
                 lock (_reentrancyBlocker)
                 {
+                    uint questionId = RandId();
+                    var question = new PendingQuestion(this, questionId, target, inParams);
+
                     while (!_questionTable.ReplacementTryAdd(questionId, question))
                     {
                         questionId = RandId();
@@ -246,9 +246,9 @@ namespace Capnp.Rpc
                         question = new PendingQuestion(this, questionId, target, inParams);
                         oldQuestion.Dispose();
                     }
-                }
 
-                return question;
+                    return question;
+                }
             }
 
             void DeleteQuestion(uint id, PendingQuestion question)
diff --git a/Capnp.Net.Runtime/Rpc/Skeleton.cs b/Capnp.Net.Runtime/Rpc/Skeleton.cs
index 2a098f9..2be39c9 100644
--- a/Capnp.Net.Runtime/Rpc/Skeleton.cs
+++ b/Capnp.Net.Runtime/Rpc/Skeleton.cs
@@ -29,7 +29,9 @@ namespace Capnp.Rpc
             }
         }
 
+#if DEBUG_DISPOSE
         const int NoDisposeFlag = 0x4000000;
+#endif
 
         static readonly ConditionalWeakTable<object, Skeleton> _implMap =
             new ConditionalWeakTable<object, Skeleton>();
@@ -61,6 +63,7 @@ namespace Capnp.Rpc
             return new SkeletonRelinquisher(GetOrCreateSkeleton(impl, true));
         }
 
+#if DEBUG_DISPOSE
         /// <summary>
         /// This DEBUG-only diagnostic method states that the Skeleton corresponding to a given capability is not expected to
         /// be disposed until the next call to EndAssertNotDisposed().
@@ -81,6 +84,7 @@ namespace Capnp.Rpc
         {
             GetOrCreateSkeleton(impl, false).EndAssertNotDisposed();
         }
+#endif
 
         int _refCount = 0;
 
@@ -99,6 +103,7 @@ namespace Capnp.Rpc
             Interlocked.Increment(ref _refCount);
         }
 
+#if DEBUG_DISPOSE
         internal void BeginAssertNotDisposed()
         {
             if ((Interlocked.Add(ref _refCount, NoDisposeFlag) & NoDisposeFlag) == 0)
@@ -113,6 +118,7 @@ namespace Capnp.Rpc
                 throw new InvalidOperationException("Flag already cleared. State is now broken.");
             }
         }
+#endif
 
         internal void Relinquish()
         {
@@ -120,8 +126,10 @@ namespace Capnp.Rpc
 
             if (0 == count)
             {
+#if DEBUG_DISPOSE
                 if ((count & NoDisposeFlag) != 0)
                     throw new InvalidOperationException("Unexpected Skeleton disposal");
+#endif
 
                 Dispose(true);
                 GC.SuppressFinalize(this);