When using iOS app on a very slow but still continuous internet connection with high roundtrip delay such as VSAT/Iridium/Inmarsat (and also possibly rural GPRS/Edge or CDMA450 and similar) the app will sense that it has network availability but the high ping and low transfer rate will lock up the UI responsiveness for about 15 second up to a minute or more as the network stack is working to update playlists and syncing and whatnot in the background, as these tasks happens more or less instantly on a normal HSPA or wired connection most people will never notice this "bug" (more of a bad design maybe).

However considering the large amount of customers using satellite internet on cruise ships (Oasis of the Sea etc) and transatlantic jets etc this is something that should be dealt with. While the customer might not even want the use the network feature but is still connected to the cruise ship or jetliners wifi but is expecting fluid offline behaviour from the app. The way to work around this issue is of course to disconnect the wifi or entering airplane mode to force the app to into offline mode directly upon launch. It is stupid to have to do this all the time. And as soon as the app detects the connection is live it will freeze up.