I have a really bizarre issue that I've had the damndest time trying to isolate.

I have two HTC Hero phones in my house (mine and my wife's). Both of us can send and receive MMS messages from each other without any problem. However when my brother, who is using an HTC Incredible on the Verizon network, sends an MMS message to us I can see the message just fine but on my wife's Hero there is a big gray "Play" logo. If you tap the logo the screen goes black (and sometimes will very briefly flash a portion of the txt message attached to the MMS). Then the screen flickers and you're back at the main menu of the stock messaging app (not even in the messaging thread you were reading).

What gives? We're both running the Cyanogen mod, the exact same release, with the exact same phone, with the exact same stock messaging application? I've researched the play button issue on this forum and others but there seems to be no consistency between what people say they think is causing it and nobody has had multiple Hero units to compare/contrast with.

Where should I even start investigating this? It's a really frustrating quirk.