Airplay problems continue under Mountain Lion, iOS 6, Pioneer VSX 1021 K

There's several threads about getting previously working VSX 1021 models to play Airplay music here, and elsewhere on the internet. For some, turning of IPv6 worked. For some updated iOS or iTunes worked. For some, turning off Multicast or the IGMP Proxy in the router worked. For me, nothing has worked.

When initially got the receiver and was using iOS 5.x on my iPhone, the receiver could be off, and selecting it as an Airplay source would boot it, pause for a few seconds while it did so, then play music. It also worked fine from my computer. Now months later, many iOS updates later, it rarely works. Sometimes I can get it to work if I turn on the receiver, set it to HMG mode, then turn on my iPhone or iTunes, then select it as a source, then click play. Often this does not work, or I need a TV on connected to the receiver, or turning the receiver off then on again will work. However there's obviously something wrong, and something that I'm not noticing.

If I turn the VSX on and put it in HMG mode, then play Airplay to it from any device, it will switch to the Now Playing screen and say connected to the network. The track title does not come up, the album artwork does not come up, the progress bar does not advance (although it does on the iPhone or in iTunes). If you deselect the VSX as the Airplay source, play a new song, then select the VSX as the source again, the TV screen updates, but with the _previous_ info, ie the first song title, and the album artwork for the last song I tried to play. It still never plays. It's almost comical how confused it is: my iphone is playing Smashing Pumpkins set to the VSX as Airplay source, the TV shows Aesop Rock is the song title playing, and the album art is a Tool cover.

I'm at a loss. I think with Lion, iOS 5 and iTunes 10.x this would work again. As it stands, I have a new phone that has to run iOS 6, and my computer is updated to Mountain Lion and iTunes 11. My receiver, which used to be so boss (walk in the door with headphones, unplug them and select the VSX and after a brief pause the music would keep playing, nice!), is now just such a disappointment. Any thoughts?

Thanks for reading,

DD