diff --git a/RxSwift/Observables/Multicast.swift b/RxSwift/Observables/Multicast.swift
index 279291c4b..ccbcb4510 100644
--- a/RxSwift/Observables/Multicast.swift
+++ b/RxSwift/Observables/Multicast.swift
@@ -124,6 +124,9 @@ final fileprivate class RefCountSink<CO: ConnectableObservableType, O: ObserverT
 
     func run() -> Disposable {
         let subscription = _parent._source.subscribe(self)
+        if self.disposed {
+            return Disposables.create()
+        }
 
         _parent._lock.lock(); defer { _parent._lock.unlock() } // {
         if _parent._count == 0 {
diff --git a/Tests/RxSwiftTests/Observable+ShareReplay1Tests.swift b/Tests/RxSwiftTests/Observable+ShareReplay1Tests.swift
index 6049c69d8..d2b1d9895 100644
--- a/Tests/RxSwiftTests/Observable+ShareReplay1Tests.swift
+++ b/Tests/RxSwiftTests/Observable+ShareReplay1Tests.swift
@@ -205,14 +205,7 @@ extension ObservableShareReplay1Test {
                 ])
 
             // unoptimized version of replay subject will make a subscription and kill it immediately
-            XCTAssertEqual(xs.subscriptions[0], Subscription(335, 365))
-
-            switch version {
-            case .composition:
-                XCTAssertTrue(xs.subscriptions.count == 2 && xs.subscriptions[1] == Subscription(440, 440))
-            case .optimized:
-                XCTAssertTrue(xs.subscriptions.count == 1)
-            }
+            XCTAssertEqual(xs.subscriptions, [Subscription(335, 365)])
         }
     }
 
@@ -275,15 +268,7 @@ extension ObservableShareReplay1Test {
                 completed(365)
                 ])
 
-            XCTAssertEqual(xs.subscriptions[0], Subscription(335, 365))
-
-            // unoptimized version of replay subject will make a subscription and kill it immediately
-            switch version {
-            case .composition:
-                XCTAssertTrue(xs.subscriptions.count == 2 && xs.subscriptions[1] == Subscription(440, 440))
-            case .optimized:
-                XCTAssertTrue(xs.subscriptions.count == 1)
-            }
+            XCTAssertEqual(xs.subscriptions, [Subscription(335, 365)])
         }
     }
 
@@ -401,18 +386,10 @@ extension ObservableShareReplay1Test {
                 completed(365)
                 ])
 
-            XCTAssertEqual(xs.subscriptions[0], Subscription(335, 365))
-            
-            // unoptimized version of replay subject will make a subscription and kill it immediately
-            switch version {
-            case .composition:
-                XCTAssertTrue(xs.subscriptions.count == 2 && xs.subscriptions[1] == Subscription(440, 440))
-            case .optimized:
-                XCTAssertTrue(xs.subscriptions.count == 1)
-            }
+            XCTAssertEqual(xs.subscriptions, [Subscription(335, 365)])
         }
     }
-    
+
     #if TRACE_RESOURCES
         func testShareReplayReleasesResourcesOnComplete() {
             _ = Observable<Int>.just(1).shareReplay(1).subscribe()