This update is recommended for owners of MacBook, MacBook Air, and MacBook Pro with Mini DisplayPort. The update addresses an issue where some standard definition purchases from the iTunes Store do not play on some external displays.

It should be emphasized that this only resolves issues with standard definition versions of purchases. So, if you were having troubles before and are now hoping to watch that download in all its high definition glory, you are still out of luck.

The update is currently only available via Software Update for all Mini DisplayPort equipped systems.

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In what seems like another addition to a long list of examples of how when you rent digital content, you’re actually renting it with a strict set of conditions, Apple owners are running into trouble with High Definition Content Protection (HDCP). The problem, affecting owners of the new aluminum MacBooks and MacBook Pro, occurs when you try to play some iTunes-rented movies on an external display attached to your notebook.

The HDCP causing the problem is intended to prevent copying high-def content across an HDMI connection. It’s also included in DisplayPort tech, which is the new standard for video output on current generation Mac portable computers. According to Ars Technica, the problem seems to affect movies protected by Apple’s FairPlay Version 3 DRM, although not all files which have Version 3 protection are affected. Whether or not the movie plays appears to be somewhat random, at least in Ars’ limited sample pool.

The person who pointed out the problem to Ars was just trying to play Hellboy 2 for a class of high school students using an external projector. Another case reported in an Apple support discussion thread occurred when a MacBook owner tried to playback content to his external 19-inch monitor. This report was quickly joined by many, many others. In all cases, playback works fine on the computer’s built-in display.

Is there a fix?

Is this another issue to be resolved quickly and with relatively little stir, like the trackpad hard-click recognition problem? Likely not, since a fix in this case might open up rental HD content to potential piracy. A software solution would take more time and attention to preserve HDCP integrity while allowing proper use for those who rented content and have no intentions of copying the content.

That’s not to say that Apple can let this one pass. One of the great incentives to even rent movies through iTunes is the ability to play it back on your HDTV or projector. If new MacBook owners (who represent a very sizeable group) feel like they’re playing Russian roulette when they rent content from iTunes, they’d simply stop doing it. And those caught unaware will go back to Apple for some kind of compensation and possibly swear off the service for good. Some angry MacBook owners are already seeing this as a ploy to get people to buy AppleTVs. This is probably not the case, but even the impression that it might be is damaging.

In a time when many are turning to their computers as home theater supplements and substitutes, Apple would do well to nip this in the bud right away. Since some movies do and some don’t encounter the HDCP problem, it may be a studio issue and out of their hands. If it is, they’ll have to lobby the studios, paint a picture of lost revenue, and hope to pressure a switch in the encoding of affected movies.

What do you say? Does this HDCP mess have you looking to jump the iTunes ship, or do you trust in an Apple fix?

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