diff --git a/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.h b/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.h
index ff38628..a2064df 100644
--- a/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.h
+++ b/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.h
@@ -15,6 +15,7 @@
 @interface RTCUIApplicationStatusObserver : NSObject
 
 + (instancetype)sharedInstance;
++ (void)prepareForUse;
 
 - (BOOL)isApplicationActive;
 
diff --git a/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.m b/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.m
index 1d2aab4..7134773 100644
--- a/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.m
+++ b/sdk/objc/Framework/Classes/Common/RTCUIApplicationStatusObserver.m
@@ -26,6 +26,7 @@
 @implementation RTCUIApplicationStatusObserver {
   BOOL _initialized;
   dispatch_block_t _initializeBlock;
+  dispatch_semaphore_t _waitForInitializeSemaphore;
   UIApplicationState _state;
 
   id<NSObject> _activeObserver;
@@ -45,6 +46,12 @@
   return sharedInstance;
 }
 
+// Method to make sure observers are added and the initialization block is
+// scheduled to run on the main queue.
++ (void)prepareForUse {
+  __unused RTCUIApplicationStatusObserver *observer = [self sharedInstance];
+}
+
 - (id)init {
   if (self = [super init]) {
     NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
@@ -65,6 +72,7 @@
                                                 [UIApplication sharedApplication].applicationState;
                                           }];
 
+    _waitForInitializeSemaphore = dispatch_semaphore_create(1);
     _initialized = NO;
     _initializeBlock = dispatch_block_create(DISPATCH_BLOCK_INHERIT_QOS_CLASS, ^{
       weakSelf.state = [UIApplication sharedApplication].applicationState;
@@ -84,10 +92,19 @@
 }
 
 - (BOOL)isApplicationActive {
+  // NOTE: The function `dispatch_block_wait` can only legally be called once.
+  // Because of this, if several threads call the `isApplicationActive` method before
+  // the `_initializeBlock` has been executed, instead of multiple threads calling
+  // `dispatch_block_wait`, the other threads need to wait for the first waiting thread
+  // instead.
   if (!_initialized) {
-    long ret = dispatch_block_wait(_initializeBlock,
-                                   dispatch_time(DISPATCH_TIME_NOW, 10.0 * NSEC_PER_SEC));
-    RTC_DCHECK_EQ(ret, 0);
+    dispatch_semaphore_wait(_waitForInitializeSemaphore, DISPATCH_TIME_FOREVER);
+    if (!_initialized) {
+      long ret = dispatch_block_wait(_initializeBlock,
+                                     dispatch_time(DISPATCH_TIME_NOW, 10.0 * NSEC_PER_SEC));
+      RTC_DCHECK_EQ(ret, 0);
+    }
+    dispatch_semaphore_signal(_waitForInitializeSemaphore);
   }
   return _state == UIApplicationStateActive;
 }
diff --git a/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoDecoderH264.mm b/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoDecoderH264.mm
index f657f9c..b19cb43 100644
--- a/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoDecoderH264.mm
+++ b/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoDecoderH264.mm
@@ -67,6 +67,16 @@
   RTCVideoDecoderCallback _callback;
 }
 
+- (instancetype)init {
+  if (self = [super init]) {
+#if defined(WEBRTC_IOS)
+    [RTCUIApplicationStatusObserver prepareForUse];
+#endif
+  }
+
+  return self;
+}
+
 - (void)dealloc {
   [self destroyDecompressionSession];
   [self setVideoFormat:nullptr];
diff --git a/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoEncoderH264.mm b/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoEncoderH264.mm
index 0fcefee..6e2b568 100644
--- a/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoEncoderH264.mm
+++ b/sdk/objc/Framework/Classes/VideoToolbox/RTCVideoEncoderH264.mm
@@ -301,6 +301,10 @@
     _profile = ExtractProfile([codecInfo nativeVideoCodec]);
     LOG(LS_INFO) << "Using profile " << CFStringToString(_profile);
     RTC_CHECK([codecInfo.name isEqualToString:@"H264"]);
+
+#if defined(WEBRTC_IOS)
+    [RTCUIApplicationStatusObserver prepareForUse];
+#endif
   }
   return self;
 }