diff --git a/Podfile b/Podfile
index a095f7f57..b934649d5 100644
--- a/Podfile
+++ b/Podfile
@@ -5,8 +5,7 @@ target 'Signal' do
     pod 'SocketRocket',               :git => 'https://github.com/facebook/SocketRocket.git'
     pod 'AxolotlKit',                 git: 'https://github.com/WhisperSystems/SignalProtocolKit.git'
     #pod 'AxolotlKit',                 path: '../SignalProtocolKit'
-    #pod 'SignalServiceKit',           git: 'https://github.com/WhisperSystems/SignalServiceKit.git', branch: 'mkirk/webrtc'
-    pod 'SignalServiceKit',           git: 'https://github.com/WhisperSystems/SignalServiceKit.git', branch: 'charlesmchen/webrtc/threadSafety'
+    pod 'SignalServiceKit',           git: 'https://github.com/WhisperSystems/SignalServiceKit.git', branch: 'mkirk/webrtc'
     #pod 'SignalServiceKit',           path: '../SignalServiceKit'
     pod 'OpenSSL'
     pod 'PastelogKit',                '~> 1.3'
diff --git a/Podfile.lock b/Podfile.lock
index 8cd84ef2d..6bd95ac67 100644
--- a/Podfile.lock
+++ b/Podfile.lock
@@ -123,7 +123,7 @@ DEPENDENCIES:
   - PastelogKit (~> 1.3)
   - PureLayout
   - SCWaveformView (~> 1.0)
-  - SignalServiceKit (from `https://github.com/WhisperSystems/SignalServiceKit.git`, branch `charlesmchen/webrtc/threadSafety`)
+  - SignalServiceKit (from `https://github.com/WhisperSystems/SignalServiceKit.git`, branch `mkirk/webrtc`)
   - SocketRocket (from `https://github.com/facebook/SocketRocket.git`)
   - ZXingObjC
 
@@ -131,7 +131,7 @@ EXTERNAL SOURCES:
   AxolotlKit:
     :git: https://github.com/WhisperSystems/SignalProtocolKit.git
   SignalServiceKit:
-    :branch: charlesmchen/webrtc/threadSafety
+    :branch: mkirk/webrtc
     :git: https://github.com/WhisperSystems/SignalServiceKit.git
   SocketRocket:
     :git: https://github.com/facebook/SocketRocket.git
@@ -141,7 +141,7 @@ CHECKOUT OPTIONS:
     :commit: 919d541d6b8a8802a94f943026b8f68394e2c0b8
     :git: https://github.com/WhisperSystems/SignalProtocolKit.git
   SignalServiceKit:
-    :commit: ddbc4819f1aa10e0164c1591dfc12cba49e04ed0
+    :commit: 7ca1d5e8a62273b524281d905c560b08c7c22039
     :git: https://github.com/WhisperSystems/SignalServiceKit.git
   SocketRocket:
     :commit: 41b57bb2fc292a814f758441a05243eb38457027
@@ -173,6 +173,6 @@ SPEC CHECKSUMS:
   YapDatabase: b1e43555a34a5298e23a045be96817a5ef0da58f
   ZXingObjC: bf15b3814f7a105b6d99f47da2333c93a063650a
 
-PODFILE CHECKSUM: beb37f2fe7d11b6d2a8124b03b20f903908fd8aa
+PODFILE CHECKSUM: 9f2e2cf6d4db276e3d0280343260503d09c72979
 
 COCOAPODS: 1.0.1
diff --git a/Signal/src/call/CallService.swift b/Signal/src/call/CallService.swift
index 2345f8a9a..2e3ed4663 100644
--- a/Signal/src/call/CallService.swift
+++ b/Signal/src/call/CallService.swift
@@ -635,11 +635,7 @@ protocol CallServiceObserver: class {
         callRecord.save()
 
         let message = DataChannelMessage.forConnected(callId: call.signalingId)
-        peerConnectionClient.sendDataChannelMessage(data: message.asData()).then { _ in
-            Logger.debug("\(self.TAG) sendDataChannelMessage succeeded")
-            }.catch(on: DispatchQueue.main) { _ in
-                Logger.warn("\(self.TAG) sendDataChannelMessage failed")
-        }
+        peerConnectionClient.sendDataChannelMessage(data: message.asData())
 
         handleConnectedCall(call)
     }
@@ -737,11 +733,7 @@ protocol CallServiceObserver: class {
 
         // If the call is connected, we can send the hangup via the data channel.
         let message = DataChannelMessage.forHangup(callId: call.signalingId)
-        peerConnectionClient.sendDataChannelMessage(data: message.asData()).then { _ in
-            Logger.debug("\(self.TAG) sendDataChannelMessage succeeded")
-            }.catch(on: DispatchQueue.main) { _ in
-                Logger.warn("\(self.TAG) sendDataChannelMessage failed")
-        }
+        peerConnectionClient.sendDataChannelMessage(data: message.asData())
 
         // If the call hasn't started yet, we don't have a data channel to communicate the hang up. Use Signal Service Message.
         let hangupMessage = OWSCallHangupMessage(callId: call.signalingId)
@@ -1075,11 +1067,7 @@ protocol CallServiceObserver: class {
         self.peerConnectionClient?.setLocalVideoEnabled(enabled: shouldHaveLocalVideoTrack)
 
         let message = DataChannelMessage.forVideoStreamingStatus(callId: call.signalingId, enabled:shouldHaveLocalVideoTrack)
-        peerConnectionClient.sendDataChannelMessage(data: message.asData()).then { _ in
-            Logger.debug("\(self.TAG) sendDataChannelMessage succeeded")
-            }.catch(on: DispatchQueue.main) { _ in
-                Logger.warn("\(self.TAG) sendDataChannelMessage failed")
-        }
+        peerConnectionClient.sendDataChannelMessage(data: message.asData())
     }
 
     // MARK: - Observers
diff --git a/Signal/src/call/PeerConnectionClient.swift b/Signal/src/call/PeerConnectionClient.swift
index e5852806e..3ff27d3d7 100644
--- a/Signal/src/call/PeerConnectionClient.swift
+++ b/Signal/src/call/PeerConnectionClient.swift
@@ -18,6 +18,8 @@ let kMediaConstraintsMaxHeight = kRTCMediaConstraintsMaxHeight
 
 /**
  * The PeerConnectionClient notifies it's delegate (the CallService) of key events in the call signaling life cycle
+ *
+ * The delegate's methods will always be called on the main thread.
  */
 protocol PeerConnectionClientDelegate: class {
 
@@ -143,7 +145,7 @@ class PeerConnectionClient: NSObject, RTCPeerConnectionDelegate, RTCDataChannelD
 
     public func createSignalingDataChannel() {
         AssertIsOnMainThread()
-        
+
         PeerConnectionClient.signalingQueue.sync {
             let dataChannel = peerConnection.dataChannel(forLabel: Identifiers.dataChannelSignaling.rawValue,
                                                          configuration: RTCDataChannelConfiguration())
@@ -404,24 +406,24 @@ class PeerConnectionClient: NSObject, RTCPeerConnectionDelegate, RTCDataChannelD
 
     // MARK: - Data Channel
 
-    public func sendDataChannelMessage(data: Data) -> Promise<Bool> {
+    public func sendDataChannelMessage(data: Data) {
         AssertIsOnMainThread()
-        
-        return Promise { fulfill, reject in
-            AssertIsOnMainThread()
-            
-            PeerConnectionClient.signalingQueue.async {
-                self.assertOnSignalingQueue()
 
-                guard let dataChannel = self.dataChannel else {
-                    Logger.error("\(self.TAG) in \(#function) ignoring sending \(data) for nil dataChannel")
-                    reject(OWSErrorMakeWebRTCMissingDataChannelError())
-                    return
-                }
-                
-                let buffer = RTCDataBuffer(data: data, isBinary: false)
-                let result = dataChannel.sendData(buffer)
-                fulfill(result)
+        PeerConnectionClient.signalingQueue.async {
+            self.assertOnSignalingQueue()
+
+            guard let dataChannel = self.dataChannel else {
+                Logger.error("\(self.TAG) in \(#function) ignoring sending \(data) for nil dataChannel")
+                return
+            }
+
+            let buffer = RTCDataBuffer(data: data, isBinary: false)
+            let result = dataChannel.sendData(buffer)
+
+            if result {
+                Logger.debug("\(self.TAG) sendDataChannelMessage succeeded")
+            } else {
+                Logger.warn("\(self.TAG) sendDataChannelMessage failed")
             }
         }
     }
diff --git a/Signal/translations/en.lproj/Localizable.strings b/Signal/translations/en.lproj/Localizable.strings
index 7618241da..f5bd472fc 100644
--- a/Signal/translations/en.lproj/Localizable.strings
+++ b/Signal/translations/en.lproj/Localizable.strings
@@ -250,9 +250,6 @@
 /* Error message when attempting to send message */
 "ERROR_DESCRIPTION_UNREGISTERED_RECIPIENT" = "Recipient is no longer a Signal user.";
 
-/* Missing data channel while trying to sending message */
-"ERROR_DESCRIPTION_WEBRTC_MISSING_DATA_CHANNEL" = "Missing connection";
-
 /* No comment provided by engineer. */
 "ERROR_MESSAGE_DUPLICATE_MESSAGE" = "Received a duplicated message.";