I noticed the following behavior today:
I selected random playback, the first song began to cache and the title appeared momentarily, then my stereo's display switched to the default of "NO NAME". Subsequent tracks displayed NO NAME as well.
It seems like the metadata is getting there, but then goes away.
Also, when metadata does work normally, I am having the problem with preloading on 5.6 as discussed in this thread: http://forum.madsonic.org/viewtopic.php?f=40&t=1065
. It seems like, while looking at the Util.java source on github, at line 1221: avrcpIntent.putExtra("id", (long) downloadService.getCurrentPlayingIndex()+1);
the +1 is refers to the next track in the play queue as opposed to the currently playing track. Could this be creating that bug?