HDMI Blink

  • Hi Everyone,

    I am having a lot of trouble getting Kodi to work on one of my TVs. The TV is a 40" Sony Bravia and the PC is a Foxconn NT3700 running libreelec.

    From what I have found online, I am experiencing something called 'HDMI Blink'. The screen will go black for a fraction of a second at random intervals. This happens regardless of what I am playing in Kodi, it even happens on the menu screens. This appears to be a common problem with Xbox One consoles and is apparently due to manufacturers not all supporting the same HDMI specifications properly.

    I have changed HDMI cables and swapped the pc for another of the same model but the problem is still there with this one TV. If I connect the unit to the bedroom TV it works fine.

    The unit does have a DVI output and a VGA output. Unfortunately the TV does not support more than 720 lines on the VGA connector. :(

    Does anyone know a solution?

    I only have two options as far as I am aware:

    Use DVI to HDMI. But how do I get audio?

    Use VGA to SCART. My TV supports 1080 lines over SCART as verified by my xbox 360.

    However, although I can set the resolution to 576 or 1080 lines, set the Vertical sync to 50Hz but I cannot set the Horizontal Sync frequency from 31KHz to 15.6KHz in the LibreElec menu. There is no option. How can I find out if my card supports this option and how can I set it?

  • saw similar scenario on an older 720p lg with latest kodi android rk3328/oreo and as well on amlogic s905x libreelec 8.2.5 with same cable and tv. Blinks to black display then back on. But works fine on rpi with same hdmi cable and tv with 8.2.5.

    Never tested with new cable yet.

  • However, although I can set the resolution to 576 or 1080 lines, set the Vertical sync to 50Hz but I cannot set the Horizontal Sync frequency from 31KHz to 15.6KHz in the LibreElec menu. There is no option. How can I find out if my card supports this option and how can I set it?

    Yes, there is no option for horizontal frequencies.

    You will find this XML tag in your guisettings.xml:

    Code
    <setting id="videoscreen.whitelist">

    It contains all possible resolutions / vertical frequencies for the output device.

    If whitelist changes from time to time with the same output device, it indicates a connection problem.

  • Yes, there is no option for horizontal frequencies.

    You will find this XML tag in your guisettings.xml:

    Code
    <setting id="videoscreen.whitelist">

    It contains all possible resolutions / vertical frequencies for the output device.

    If whitelist changes from time to time with the same output device, it indicates a connection problem.

    I do not have that option. I checked in /storage/.kodi/userdata/guisettings.xml and I only have this reference to videoscreen:

    <videoscreen>

    <blankdisplays default="true">false</blankdisplays>

    <cms3dlut default="true"></cms3dlut>

    <cmsenabled default="true">false</cmsenabled>

    <cmsgamma default="true">220</cmsgamma>

    <cmsgammamode default="true">0</cmsgammamode>

    <cmslutsize default="true">6</cmslutsize>

    <cmsmode default="true">0</cmsmode>

    <cmsprimaries default="true">0</cmsprimaries>

    <cmswhitepoint default="true">0</cmswhitepoint>

    <delayrefreshchange default="true">0</delayrefreshchange>

    <displayprofile default="true"></displayprofile>

    <dither default="true">false</dither>

    <ditherdepth default="true">8</ditherdepth>

    <fakefullscreen default="true">true</fakefullscreen>

    <limitedrange default="true">false</limitedrange>

    <monitor default="true">Default</monitor>

    <noofbuffers default="true">2</noofbuffers>

    <preferedstereoscopicmode default="true">100</preferedstereoscopicmode>

    <resolution default="true">16</resolution>

    <screen default="true">0</screen>

    <screenmode default="true">DESKTOP</screenmode>

    <stereoscopicmode default="true">0</stereoscopicmode>

    </videoscreen>

  • You did the right hardware tests. Because it works with your other TV, I think the cause is bad HDMI communication of your Sony TV. You don't have a whitelist in your guisettings.xml, because the Sony TV doesn't transmit the possible screen modes, I guess.

    If you would try VGA, there will be no whitelist transmission. If you would try DVI <---> HDMI, it would basically work like HDMI, with no whitelist, too.

    I had a conversation with another user without whitelist. At the end I gave him a weird idea, but it's still untested.

  • Yes I think that this is due to an incompatibility with the HDMI version in the pc and in the TV. I have seen a lot of people on Facebook and other forums with this exact issue with the Xbox One.

    Apparently, so I have been told it is to do with the different revisions of HDMI supporting different DMCA methods and it is up to the driver developers to add compliant support for older or later versions.

    The dummy plug might help. Will try that as plan B.

    For now I have ordered eBay.co.uk item 323405116200 DVI to HDMI

    This adapter supports audio so when it arrives I will see if my video card outputs audio on DVI.

    Is there a way to check this via a command?

    lspci says: Advanced Micro Devices, Inc. [AMD/ATI] Wrestler [Radeon HD 6320]

    Alternatively I have seen some VGA + audio to HDMI devices. Might be plan C.

  • Hello all,

    I am new to the forum and it looks like I have the same issue.

    With an odroid C2 running libreelec 8.2.5 and Kodi 17 (bought to play 4K videos), I encounter the same issue : from time to time, the image disappears for a few seconds. Most of the time, the sound remains even if I can lose 1 or 2 seconds. I cannot watch a full movie without issue and it happens as well when playing in libreelec menus.

    My TV is a Samung UE50KU6000.

    I am attaching a debug log just in case someone can help.

  • OK, so I ordered a DVI to HDMI adapter, I connected this to the DVI port of my Foxconn Nettop 3700 and then the HDMI from the adapter to the TV.

    I can confirm that this adapter and my PC supports sound via DVI. However the HDMI blinking problem is still there.

    Again I changed the HDMI cable and tried all of the ports on my TV. blinking still happens.

    Also tried the other identical PC from the bedroom again with this adapter. Same problem in living room, working fine in bedroom.

    Plan B

    I have ordered a HDMI dummy plug to see if that will work.

    Plan C

    Using the PC through VGA on the living room TV has no problem working at all. Unfortunately my TV will only accept 1024x768 via the VGA socket, even though it is a 1080p tv, so I have also ordered a VGA + audio to HDMI adapter.


    My friend brought his XBOX one round to try because he has this same problem with his XBOX and his brand new Samsung TV. The blinking also happens on the XBOX one with my TV. I have yet to test my Foxconn PC on his TV but it looks like there is a connection here (or lack of lol).

  • OK so the HDMI dummy plug had no effect whatsoever.

    Adapting VGA and audio to HDMI had no effect either.

    So the fault, I would assume at this point, must be with the way that the TV is receiving the HDMI stream.

    Now if it was just my TV I would think it may have been a fault with a component inside it. But this is happening to two of my friends with Xbox One. One of them has a brand new TV. He has even exchanged it and it still happens on his TV.

    I have tried my Kodi box on both friend's TVs and the blinking problem happens for them too. Also on their Xbox Ones but not for PS4. Weird right?


    Anyone have a clue what is happening? sounds like some kind of HDMI version compatibility perhaps? But then why would it not be compatible with a brand new AND and old TV?

    I wouldn't have a clue how to test this.

    All above devices work fine on my 2007 cheapo Argos TV using HDMI, so I don't the devices are faulty.

  • Thanks for the tests! I think the HDMI dummy plug doesn't works, because other screen modes from the TV overwrite the fixed mode of the dummy plug. If we could force the TV only to receive HDMI data, then it might be OK.

    My next theory is that newer TV's have higher HDMI transmission speed, compared to older ones. You have been tried different HDMI cables. Be sure that the HDMI cable complies the newest HDMI standard for high speed transmission.

  • Hello all,

    I am new to the forum and it looks like I have the same issue.

    With an odroid C2 running libreelec 8.2.5 and Kodi 17 (bought to play 4K videos), I encounter the same issue : from time to time, the image disappears for a few seconds. Most of the time, the sound remains even if I can lose 1 or 2 seconds. I cannot watch a full movie without issue and it happens as well when playing in libreelec menus.

    My TV is a Samung UE50KU6000.

    I am attaching a debug log just in case someone can help.

    Pretty much the same exact setup here with the same symptoms. Any luck in resolving the blink issue? When it happens frequently, rebooting the odroid-c2 seems to help reduce the blinks significantly for a while, but they always return. Issue exists with both 8.2.5 and 9.0.1

  • On the Odroid-C2 connected to a Samsung LNT4661FX/XAC TV, the HDMI blink issue appears to be resolved after I changed the refresh rate in Kodi display settings from 60 fps to 59.94 fps. Perhaps the same change will resolve it for others experiencing the same issue.