Wobbly picture with ATV2 - anyone else?

I got my new Apple TV gen 2 today and hooked it up in place of the old one. The picture was wavy. I removed the HDMI switch from the equation, no dice. I swapped cables, no dice.

The only issue I can think of (besides bad hardware) is that I use an HDMI->DVI cable for the last leg to my TV. It's not a converter, it is fully HDCP aware, and it works fine with ATV G1 and a Roku for Netflix HD streaming.

Unfortunately I don't have a different TV to check this out with at the moment.

Is anyone else having this problem?

iMac 20", Mac OS X (10.6.4)

Posted on Sep 29, 2010 11:00 AM

Reply
204 replies

Nov 22, 2010 5:20 PM in response to TR Thompson

Well, I guess this is a half-baked fix, but at least it's a start.

The "waves" have indeed disappeared, so my Apple TV is at least watchable now. Unfortunately, it sends a 480p signal instead of 720p. So, apparently no HD for owners of older tv sets, only standard definition.

My television set doesn't display 720p (it displays 540p and 1080i), but it definitely supports 720p input (as stated in the tv's manual, and which I have tested with several upconverting DVD players in the past). It can accept 720p signal without problems and internally convert to 540p or 1080i.

Every other piece of video hardware I have ever tested on this tv has worked fine at all possible resolutions (except 1080p, of course), so I don't know why it is so difficult for Apple's engineers to get this working with the Apple TV. Hopefully, a future update will provide a definitive fix to this.

Nov 22, 2010 6:56 PM in response to Shirley 123

Look in Settings>General>About for the resolution the ATV2 is supplying. To answer your other question, I used to have wobbly video (and no sound) with my HDMI->DVI cable directly connected to the TV, but I fixed it (and got audio) with an HDMI switch box. That was before the upgrade. After the upgrade, I get steady 420p video (with no audio) connected directly and 720p video and audio through the HDMI switch, but there is a magenta color cast.

Nov 23, 2010 9:45 AM in response to JustReel Films

same here

I am having the same issues. Had waivey lines on going HDMI to DVI on original OS to my 7 year old Sony Wega. Bought the monorpice switcher, it fixed my wavey lines and I got a 720P signal (plus was able to switch between inputs). Updated to 4.1 (4.2)... and Get purple screen at 720p or bypass the switcher and get 480p (w/o purple). Very frustrating. I tried someones suggestions on the booting up order, I still got the purple screen... My other workaround suggestion is to go direct to tv (by pass switcher)... restart ATV2... set ATV2 to NEVER sleep, then switch the cables back through the switcher. Still only gives me 480, but lets me switch back and forth. I will try monoprice today and see what they have to say....

If someone knows of a fix (even if jb'ing is required) please post.

and where are my Apps?

Nov 23, 2010 11:09 AM in response to ringonbob

About that boot order, its all about timing.

-Have both ATV and HDMI switcher switched off. Make sure the switcher source input is already set to ATV.

-Get the ATV remote and the HDMI switcher remote in each hand.

-Turn on ATV by pressing the center button, as soon as you lift up your finger on that button, _wait about half a second_ then turn on the HDMI switcher.

You should see something on the screen in about 8 seconds.

I had success trying this last night, and tried many combinations( turn on both units at exact same time, waiting 10 seconds then turn on, etc, etc.)
then finally got 720p without the color problem.

So basically:

-AppleTV ON
-wait 0.5 second
-HDMI switcher ON
-wait 8 seconds
-Success!

I'll see if I can post a video to show this.

BTW I have a Sony Wega HDTV KF-42we610 which is about 7 year old.

Nov 23, 2010 12:46 PM in response to David M.F. Chapman

Remote button mashing, bruteforce port switching, eventually I found one that worked out and tried to replicate my actions. 🙂

Everytime you wake up ATV, it goes through a series of checklists such as initializing network, display etc. Before it displays anything on the screen, it challenges the HDMI port to give a response. It first asks the TV to spit out EDID data which is a list of compatible resolutions. The ATV had trouble getting that information so it defaulted to 480p along with incorrect clock phase. Hence the wavy lines. I think the firmware just adjusted the clock value but still couldn't detect the TV's EDID. Monoprice's HDMI switcher can detect the EDID of the older generation TVs (maybe it has extra chipsets that ATV does not have) so it can report it properly to ATV.

As for the color problem, the data packets color encoding is shifted because it relies on the proper clock rate. I guess the HDMI switcher only reports it once, (when its turned on) and ATV has a time limit when to receive TV infomation. So turning on both units at the right order and time receives the data packets in time so the ATV can configure itself for display.

You can read it more about it here: http://en.wikipedia.org/wiki/Extendeddisplay_identificationdata

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Wobbly picture with ATV2 - anyone else?

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