[XMP] Ensure volume always set when driver created.

Fixes the issue of the volume starting at default and abruptly
adjusting to the game setting as it changes.

src/xenia/apu/audio_media_player.cc

@@ -245,9 +245,11 @@ void AudioMediaPlayer::Play() {
 
   if (volume_ == 0.0f) {
     volume_ = cvars::xmp_default_volume / 100.0f;
-    SetVolume(volume_);
   }
 
+  // Always apply the stored volume to the newly created driver
+  driver_->SetVolume(volume_);
+
   auto result =
       ProcessAudioLoop(this, driver_.get(), formatContext, codecContext, 0);