IDevice, HDMI & Underscan

Hi!
When mirroring an iDevice on a TV or projector using the lignthing to HDMI adapter, the image is always scaled down and displayed in the center of the screen with black bars added all the way around.
This is *not* an aspect ratio related problem because the image is clearly scaled down and black bars are added on all four sides.
I understand there is nothing really do to about it more than adjusting the TV or projector to scale up the already downscaled image, which results in a image quality loss.
When using video apps or the Lightning to VGA adapter, the problem dissaperas and the image covers the whole screen.
This is insanely frustrating and i just need to understand why this happens. Is there anyone out there with a reasonable explanation?
Best regards!

BSteely wrote:
...if there was such a widespread problem with the HDMI port on the mini, these boards would be seriously lighting up, and they're not...
If you look at the topic titles in this Mini forum, you will see a good number of people posting specifically about display/monitor compatibility issues.
It's significant enough to indicate a pattern.
During initial install, HDCP does not come into play. The HP accepts the output from the mini as being computer output and so renders it as such. On subsequent restarts, HDCP comes into effect. The HP now thinks differently of the signal it is receiving and believes it is coming from a consumer electronic box and not a computer. The HP then reacts to this difference by configuring itself differently and using settings more in keeping with CE boxes, hence overscan turns on within the HP and all sorts of other nasty, TV-like settings. That's what I believe to be happening.
Can you offer a source for this information. I have never heard of this behavior. To my knowledge, HDCP is either required, or it's not. It's not a "after a restart" situation. Certainly, a restart will trigger a renegotiation of HDCP, but I'd be surprised if there was ever an "unprotected" state.

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