Performance issues using an MPMusicPlayerController - can it be accessed in the background? - objective-c

Question

EDIT: Updating my own question with the answer I figured out months later. Short answer is no, MPMusicPlayerController forwards all calls to the main thread. But it uses a CPDistributedMessagingCenter to actually handle all operations, so one can very easily write a replacement controller that makes asynchronous calls (but it won't work for a sandboxed App Store app, as far as I know - and if it did, Apple would promptly reject it).
I'm making a simple app to control iPod playback, so I've been using an MPMusicPlayerController, which Apple states can only be used in the main thread. However, I've been experiencing some frustrating performance issues in the UI. Switching to the next or previous song is triggered by a swipe, which moves the entire display (of the song info) with it, and then updates the display for the next song when the switch is triggered. The trouble is that once the song has been changed, the UI hangs for up to a second while the song info is retrieved from the MPMusicPlayerController. I've tried most everything I can think of to optimize the code, but it seems to me that the only way to fix it is to move the MPMusicPlayerController code on to a background thread, despite Apple's instructions not to.
The code to update the display, for reference:
// Called when MPMusicPlayerControllerNowPlayingItemDidChangeNotification is received
- (void) nowPlayingDidChange {
if ([iPodMusicPlayer nowPlayingItem]) {
// Temp variables (necessary when updating the subview values in the background)
title = [[iPodMusicPlayer nowPlayingItem] valueForProperty:MPMediaItemPropertyTitle];
artist = [[iPodMusicPlayer nowPlayingItem] valueForProperty:MPMediaItemPropertyArtist];
album = [[iPodMusicPlayer nowPlayingItem] valueForProperty:MPMediaItemPropertyAlbumTitle];
artwork = [[[iPodMusicPlayer nowPlayingItem] valueForProperty:MPMediaItemPropertyArtwork] imageWithSize:CGSizeMake(VIEW_HEIGHT - (2*MARGINS), VIEW_HEIGHT - (2*MARGINS))];
length = [[[iPodMusicPlayer nowPlayingItem] valueForProperty:MPMediaItemPropertyPlaybackDuration] doubleValue];
if (updateViewInBackground)
[self performSelectorInBackground:#selector(updateSongInfo) withObject:nil];
else
[self updateSongInfo];
}
else
[self setSongInfoAsDefault];
}
- (void) updateSongInfo {
// Subviews of the UIScrollView that has performance issues
songTitle.text = title;
songArtist.text = artist;
songAlbum.text = album;
songLength.text = [self formatSongLength:length];
if (!artwork) {
if ([[UIScreen mainScreen] respondsToSelector:#selector(scale)] && [[UIScreen mainScreen] scale] == 2.00)
songArtwork.image = [UIImage imageWithContentsOfFile:
#"/System/Library/Frameworks/MediaPlayer.framework/noartplaceholder#2x.png"];
else
songArtwork.image = [UIImage imageWithContentsOfFile:
#"/System/Library/Frameworks/MediaPlayer.framework/noartplaceholder.png"];
}
else
songArtwork.image = artwork;
title = nil;
artist = nil;
album = nil;
artwork = nil;
length = 0.0;
}
Is there anything I'm missing here (ie. performance optimization when updating the UIScrollView subviews)? And if not, would it be such a bad idea to just use the MPMusicPlayerController in a background thread? I know that can lead to issues if something else is accessing the iPodMusicPlayer (shared instance of the iPod in MPMusicPlayerController), but are there any ways I could potentially work around that?
Also, this is a jailbreak tweak (a Notification Center widget), so I can make use of Apple's private frameworks if they would work better than, say, the MPMusicPlayerController class (which is fairly limited anyways) for my purposes. That also means, though, that my app will be running as a part of the SpringBoard process, so I want to be sure that my code is as safe and stable as possible (I experience 2 minute hangs whenever my code does something wrong, which I don't want happening when I release this). So if you have any suggestions, I'd really appreciate it! I can provide more code / info if necessary. Thanks!