diff --git a/app/src/main/java/com/theoplayer/android/ui/demo/MainActivity.kt b/app/src/main/java/com/theoplayer/android/ui/demo/MainActivity.kt
index ae86248..f8f579f 100644
--- a/app/src/main/java/com/theoplayer/android/ui/demo/MainActivity.kt
+++ b/app/src/main/java/com/theoplayer/android/ui/demo/MainActivity.kt
@@ -44,7 +44,7 @@ fun MainContent() {
 
     val player = rememberPlayer()
     LaunchedEffect(player, source) {
-        player.player?.source = source
+        player.source = source
     }
 
     var themeMenuOpen by remember { mutableStateOf(false) }
diff --git a/app/src/main/java/com/theoplayer/android/ui/demo/nitflex/NitflexUI.kt b/app/src/main/java/com/theoplayer/android/ui/demo/nitflex/NitflexUI.kt
index 8aed80b..39520cb 100644
--- a/app/src/main/java/com/theoplayer/android/ui/demo/nitflex/NitflexUI.kt
+++ b/app/src/main/java/com/theoplayer/android/ui/demo/nitflex/NitflexUI.kt
@@ -50,7 +50,7 @@ fun NitflexUI(
 ) {
     val player = rememberPlayer(config)
     LaunchedEffect(player, source) {
-        player.player?.source = source
+        player.source = source
     }
 
     NitflexUI(modifier = modifier, player = player, title = title)
diff --git a/ui/src/main/java/com/theoplayer/android/ui/DefaultUI.kt b/ui/src/main/java/com/theoplayer/android/ui/DefaultUI.kt
index 86c2974..e5ee866 100644
--- a/ui/src/main/java/com/theoplayer/android/ui/DefaultUI.kt
+++ b/ui/src/main/java/com/theoplayer/android/ui/DefaultUI.kt
@@ -43,7 +43,7 @@ fun DefaultUI(
 ) {
     val player = rememberPlayer(config)
     LaunchedEffect(player, source) {
-        player.player?.source = source
+        player.source = source
     }
 
     DefaultUI(modifier = modifier, player = player, title = title)
diff --git a/ui/src/main/java/com/theoplayer/android/ui/PlayButton.kt b/ui/src/main/java/com/theoplayer/android/ui/PlayButton.kt
index 90af5db..a0d6479 100644
--- a/ui/src/main/java/com/theoplayer/android/ui/PlayButton.kt
+++ b/ui/src/main/java/com/theoplayer/android/ui/PlayButton.kt
@@ -54,9 +54,9 @@ fun PlayButton(
         onClick = {
             player?.let {
                 if (it.paused) {
-                    it.player?.play()
+                    it.play()
                 } else {
-                    it.player?.pause()
+                    it.pause()
                 }
             }
         }) {
diff --git a/ui/src/main/java/com/theoplayer/android/ui/Player.kt b/ui/src/main/java/com/theoplayer/android/ui/Player.kt
index c3fae9e..be32c17 100644
--- a/ui/src/main/java/com/theoplayer/android/ui/Player.kt
+++ b/ui/src/main/java/com/theoplayer/android/ui/Player.kt
@@ -43,6 +43,7 @@ import com.theoplayer.android.api.player.track.mediatrack.quality.VideoQuality
 import com.theoplayer.android.api.player.track.texttrack.TextTrack
 import com.theoplayer.android.api.player.track.texttrack.TextTrackKind
 import com.theoplayer.android.api.player.track.texttrack.TextTrackMode
+import com.theoplayer.android.api.source.SourceDescription
 import com.theoplayer.android.api.event.track.mediatrack.audio.list.AddTrackEvent as AudioAddTrackEvent
 import com.theoplayer.android.api.event.track.mediatrack.audio.list.RemoveTrackEvent as AudioRemoveTrackEvent
 import com.theoplayer.android.api.event.track.mediatrack.audio.list.TrackListChangeEvent as AudioTrackListChangeEvent
@@ -81,6 +82,11 @@ interface Player {
      */
     val theoplayerView: THEOplayerView?
 
+    /**
+     * Returns or sets the player's source.
+     */
+    var source: SourceDescription?
+
     /**
      * Returns the raw [Cast] API of the backing THEOplayer instance.
      */
@@ -231,6 +237,16 @@ interface Player {
      */
     val castReceiverName: String?
 
+    /**
+     * Starts or resumes playback.
+     */
+    fun play()
+
+    /**
+     * Pauses playback.
+     */
+    fun pause()
+
     /**
      * Contains properties to access the current [Player].
      */
@@ -327,6 +343,7 @@ internal class PlayerImpl(override val theoplayerView: THEOplayerView?) : Player
         EventListener<ReadyStateChangeEvent> { updateCurrentTimeAndPlaybackState() }
     private val resizeListener = EventListener<ResizeEvent> { updateVideoWidthAndHeight() }
     private val sourceChangeListener = EventListener<SourceChangeEvent> {
+        _source = player?.source
         error = null
         firstPlay = false
         updateCurrentTimeAndPlaybackState()
@@ -335,6 +352,7 @@ internal class PlayerImpl(override val theoplayerView: THEOplayerView?) : Player
         updateActiveVideoTrack()
     }
     private val errorListener = EventListener<ErrorEvent> { event ->
+        _source = player?.source
         error = event.errorObject
         updateCurrentTimeAndPlaybackState()
         updateDuration()
@@ -342,6 +360,24 @@ internal class PlayerImpl(override val theoplayerView: THEOplayerView?) : Player
         updateActiveVideoTrack()
     }
 
+    override fun play() {
+        paused = false
+        player?.play()
+    }
+
+    override fun pause() {
+        paused = true
+        player?.pause()
+    }
+
+    private var _source by mutableStateOf(player?.source)
+    override var source: SourceDescription?
+        get() = _source
+        set(value) {
+            _source = value
+            player?.source = value
+        }
+
     private var _volume by mutableStateOf(1.0)
     private var _muted by mutableStateOf(false)
     override var volume: Double
diff --git a/ui/src/main/java/com/theoplayer/android/ui/UIController.kt b/ui/src/main/java/com/theoplayer/android/ui/UIController.kt
index 13e5346..72ea910 100644
--- a/ui/src/main/java/com/theoplayer/android/ui/UIController.kt
+++ b/ui/src/main/java/com/theoplayer/android/ui/UIController.kt
@@ -65,7 +65,7 @@ fun UIController(
 ) {
     val player = rememberPlayer(config)
     LaunchedEffect(player, source) {
-        player.player?.source = source
+        player.source = source
     }
 
     UIController(