Shuffled around a bit of code to remove asserts during init to make debugging easier.

src/plugins/macosmediakeys/SPMediaKeyTap.h

@@ -22,7 +22,7 @@
 -(id)initWithDelegate:(id)delegate;
 
 +(BOOL)usesGlobalMediaKeyTap;
--(void)startWatchingMediaKeys;
+-(BOOL)startWatchingMediaKeys;
 -(void)stopWatchingMediaKeys;
 -(void)handleAndReleaseMediaKeyEvent:(NSEvent *)event;
 @end

src/plugins/macosmediakeys/SPMediaKeyTap.m

@@ -60,7 +60,7 @@ static CGEventRef tapEventCallback(CGEventTapProxy proxy, CGEventType type, CGEv
 	_app_switching_ref = NULL;
 }
 
--(void)startWatchingMediaKeys;{
+-(BOOL)startWatchingMediaKeys;{
     // Prevent having multiple mediaKeys threads
     [self stopWatchingMediaKeys];
 
@@ -73,13 +73,17 @@ static CGEventRef tapEventCallback(CGEventTapProxy proxy, CGEventType type, CGEv
 								  CGEventMaskBit(NX_SYSDEFINED),
 								  tapEventCallback,
 								  self);
-	assert(_eventPort != NULL);
 
-    _eventPortSource = CFMachPortCreateRunLoopSource(kCFAllocatorSystemDefault, _eventPort, 0);
-	assert(_eventPortSource != NULL);
+	if (_eventPort) {
+		_eventPortSource = CFMachPortCreateRunLoopSource(kCFAllocatorSystemDefault, _eventPort, 0);
+		if (_eventPortSource) {
+			// Let's do this in a separate thread so that a slow app doesn't lag the event tap
+			[NSThread detachNewThreadSelector:@selector(eventTapThread) toTarget:self withObject:nil];
+			return YES;
+		}
+	}
 
-	// Let's do this in a separate thread so that a slow app doesn't lag the event tap
-	[NSThread detachNewThreadSelector:@selector(eventTapThread) toTarget:self withObject:nil];
+	return NO;
 }
 -(void)stopWatchingMediaKeys;
 {

src/plugins/macosmediakeys/plugin.mm

@@ -35,12 +35,16 @@
 #include <core/sdk/constants.h>
 #include <core/sdk/IPlugin.h>
 #include <core/sdk/IPlaybackRemote.h>
+#include <core/sdk/IDebug.h>
 #include <mutex>
 #include <iostream>
 #include "SPMediaKeyTap.h"
 
 using namespace musik::core::sdk;
 
+static const char* TAG = "macosmediakeys";
+static IDebug* debug = nullptr;
+
 struct IKeyProcessor {
     virtual void ProcessKeyCode(int keyCode) = 0;
 };
@@ -49,6 +53,7 @@ struct IKeyProcessor {
     SPMediaKeyTap* keyTap;
     IKeyProcessor* processor;
 }
+- (BOOL) register;
 - (void) unregister;
 - (void) setKeyProcessor: (IKeyProcessor*) processor;
 @end
@@ -70,16 +75,30 @@ class PlaybackRemote: public IPlaybackRemote, IKeyProcessor {
     public:
         PlaybackRemote() {
             this->mediaKeys = [[MediaKeys alloc] init];
-            [this->mediaKeys setKeyProcessor: this];
+            if ([this->mediaKeys register]) {
+                [this->mediaKeys setKeyProcessor: this];
+                debug->Info(TAG, "listening to media keys");
+            }
+            else {
+                debug->Error(TAG, "failed to register media keys listener");
+                this->Unregister();
+            }
         }
 
         virtual void Release() override {
-            [this->mediaKeys unregister];
-            [this->mediaKeys release];
-            this->mediaKeys = nullptr;
+            this->Unregister();
             delete this;
         }
 
+        void Unregister() {
+            if (this->mediaKeys) {
+                [this->mediaKeys unregister];
+                [this->mediaKeys release];
+                this->mediaKeys = nullptr;
+                debug->Info(TAG, "unregistered media keys");
+            }
+        }
+
         virtual void SetPlaybackService(IPlaybackService* playback) override {
             std::unique_lock<decltype(mutex)> lock(mutex);
             this->playback = playback;
@@ -135,10 +154,6 @@ class PlaybackRemote: public IPlaybackRemote, IKeyProcessor {
         [SPMediaKeyTap defaultMediaKeyUserBundleIdentifiers], kMediaKeyUsingBundleIdentifiersDefaultsKey,
     nil]];
 
-    if ([SPMediaKeyTap usesGlobalMediaKeyTap]) {
-        [keyTap startWatchingMediaKeys];
-    }
-
     return self;
 }
 
@@ -158,7 +173,14 @@ class PlaybackRemote: public IPlaybackRemote, IKeyProcessor {
     }
 }
 
-- (void) unregister; {
+- (BOOL) register {
+    if ([SPMediaKeyTap usesGlobalMediaKeyTap]) {
+        return [keyTap startWatchingMediaKeys];
+    }
+    return NO;
+}
+
+- (void) unregister {
     if (keyTap) {
         [keyTap stopWatchingMediaKeys];
         [keyTap release];
@@ -173,3 +195,7 @@ extern "C" IPlugin* GetPlugin() {
 extern "C" IPlaybackRemote* GetPlaybackRemote() {
     return new PlaybackRemote();
 }
+
+extern "C" void SetDebug(IDebug* debug) {
+    ::debug = debug;
+}