HDCP error using Airplay on ATV2

Not sure if there is another read that better addresses this, but this one still seems relatively current.

Tried all of the above, and still get the HDCP error.

Here's the really confusing part for me. these are MY videos!! They do not be protected in any way. And this is where it gets really weird ... Not only do they not play from the iPad and iPhone, but the also do not play from iTunes on my MacBook.

HOWEVER - when I access the very same movies directly from my ATV2 via computer sharing, these very same movies which will NOT stream from within iTunes via AirPlay, WILL stream from iTunes when accessed directly from the ATV2.

Does this make ANY sense to anybody? Why would the ATV2 use a different streaming method to play video content off the MacBook, than it does to play video initiated by AirPlay? Ridiculous.

I have also had the AirPlay and ATV2 HDCP problem when trying to play content from my iPad or Mac on my HDCP compliant TV. I solved the problem by using an HDCP compliant HDMI cable directly between the ATV2 and my TV. You need to power the ATV down while you do the cable swap then power it back up so that it will handshake with the TV.

I thought my original cable was HDCP compliant, but in spite of the fact that it was a new, fairly expensive cable from a well know cable manufacturer, it turned out that this wasn't the case.