diff --git a/e2e/test/iothub/service/RegistryManagerE2ETests.cs b/e2e/test/iothub/service/RegistryManagerE2ETests.cs
index 6a730651e5..e67c6ca723 100644
--- a/e2e/test/iothub/service/RegistryManagerE2ETests.cs
+++ b/e2e/test/iothub/service/RegistryManagerE2ETests.cs
@@ -417,7 +417,7 @@ public async Task RegistryManager_Query_Works()
         [LoggedTestMethod]
         public async Task ModulesClient_GetModulesOnDevice()
         {
-            int moduleCount = 5;
+            const int moduleCount = 2;
             string testDeviceId = $"IdentityLifecycleDevice{Guid.NewGuid()}";
             string[] testModuleIds = new string[moduleCount];
             for (int i = 0; i < moduleCount; i++)
@@ -440,6 +440,9 @@ public async Task ModulesClient_GetModulesOnDevice()
                         new Module(testDeviceId, testModuleIds[i])).ConfigureAwait(false);
                 }
 
+                // Give the hub a moment
+                await Task.Delay(250).ConfigureAwait(false);
+
                 // List the modules on the test device
                 IEnumerable<Module> modulesOnDevice = await client.GetModulesOnDeviceAsync(testDeviceId).ConfigureAwait(false);
 
@@ -450,7 +453,7 @@ public async Task ModulesClient_GetModulesOnDevice()
                 Assert.AreEqual(moduleCount, moduleIdsOnDevice.Count);
                 for (int i = 0; i < moduleCount; i++)
                 {
-                    Assert.IsTrue(moduleIdsOnDevice.Contains(testModuleIds[i]));
+                    moduleIdsOnDevice.Should().Contain(testModuleIds[i]);
                 }
             }
             finally
diff --git a/iothub/device/src/IotHubConnectionString.Core.cs b/iothub/device/src/IotHubConnectionString.Core.cs
index 70edd63dd0..543ea47c5f 100644
--- a/iothub/device/src/IotHubConnectionString.Core.cs
+++ b/iothub/device/src/IotHubConnectionString.Core.cs
@@ -19,11 +19,14 @@ Task<string> IAuthorizationProvider.GetPasswordAsync()
                 if (Logging.IsEnabled)
                     Logging.Enter(this, $"{nameof(IotHubConnectionString)}.{nameof(IAuthorizationProvider.GetPasswordAsync)}");
 
-                Debug.Assert(TokenRefresher != null);
+                Debug.Assert(
+                    !string.IsNullOrWhiteSpace(SharedAccessSignature)
+                        || TokenRefresher != null,
+                    "The token refresher and the shared access signature can't both be null");
 
                 return !string.IsNullOrWhiteSpace(SharedAccessSignature)
                     ? Task.FromResult(SharedAccessSignature)
-                    : TokenRefresher.GetTokenAsync(Audience);
+                    : TokenRefresher?.GetTokenAsync(Audience);
             }
             finally
             {