HC4 liveTV issue - distorted image

  • I'm having weird issue with HC4 image. I have sundtek skytv ultimate 6 usb stick, which I moved from old LE krypton x86 box to this new HC4. I installed the tvheadend 4.2 server and pvr client. I copied the config, as I was lazy to configure it fresh and I immediatelly noticed problems. Some channels don't start at all, some freeze the HC4, some got some weird scrambled green pattern, others like old weak analog signal overlay, but then there are channels without issue. I thought it's the sundtek driver issue. But then configured kodi on my windows laptop with tvheadend pvr client pointing to the HC4 box TVH 4.2 server and the issue got reduced to two states. Channel doesn't start, or it starts fine. So it's not the sundtek driver or it isn't sundtek driver issue only. If you let me know what to check or report, I'll.

  • I assumed, but loading the TV channel remotely from Kodi on my laptop also takes ages and for some channels it won't load it at all. Do you think this is also related to the HW video decoder on LE? I thought that raw data is from TVH is processed by a kodi on windows laptop and decoded by a video driver there and HC4 has nothing to do with that. I also noticed that if I configured TVH from scratch, it wasn't able to find TV channels that were there before. So that's why I guessed sundtek driver may be also somehow involved.

    I'll give it a try, I guess. I was just ok with LE for many years. Hope they have aeon nox silvo and sundtek driver addons...

    • Official Post

    I can't speak about sundtek support as I've never personally used their devices, but over the years we didn't see much support traffic; which either means it's reliable or nobody uses it (we have no way to know).


    On a laptop I would assume there are no hardware decode issues (not impossible, but much rarer). On the HC4 if you want to eliminate the VDEC being an issue (the green lines is a known issue) you can go into Kodi settings > Player > disable "Allow using DRM PRIME decoder" and then Kodi uses ffmpeg software decode. The HC4 should have enough grunt to handle software decode with 1080p media.

  • I already tried CE. so it has both, skin and sundtek drivers. however...
    LE played TV with issues, but at least smoothly. CE can't handle it and TV channels playback is lagging. any other up to 1080p media file is alright. I haven't yet tried anything 4K, but I doubt it will work.

    doing literally nothing, the combined CPU usage is ~50%, with TV channels playing for few seconds it goes over 100% and then lagging starts. I'll consult their forum of course, just saying.

  • Check the signal strength on the console



    for DVB-S:


    /opt/bin/mediaclient --readsignal=0 -d /dev/dvb/adapter0/frontend0 --band universal

    since libreelec uses its own plugin the /opt/bin command won't work and you can just run:

    mediaclient --readsignal=0 -d /dev/dvb/adapter0/frontend0 --band universal

  • seems quite alright. btw, when you have quad tuner available.

  • I disabled every addon that was possible to be disabled. sundtek, tvheadend, mariadb and so on. and still the CPU usage is over 40%...
    kind of disappointing. I need to go back to LE to see the difference, but I remember it was ~25% or so.
    I think, I'll use LE and use the HC4 as NAS and for now keep running old box for TVH as headless Kodi.

  • The BER should be 0 you might have to adjust your dish, check your cables or change your LNB (just a wild guess since I don't know your setup).

  • The BER should be 0 you might have to adjust your dish, check your cables or change your LNB (just a wild guess since I don't know your setup).

    well, the thing is it worked with same LNB, same cable on LE8 x86, my previous kodi box. btw I have unicable inverto LNB and I'm still waiting for the quad tuner sundtek ;)
    that BER you mentioned. could it be also responsible for the poor descrambling?

  • sorry to bother you again, may I ask why this happens? BER is is on some channels always 0, on some it's mostly 0 and for few seconds jump up and on some channels it's 50/50. if my sat dish is misaligned, wouldn't I see BER alwyas and everywhere?


  • The BER should be 0 you might have to adjust your dish, check your cables or change your LNB (just a wild guess since I don't know your setup).

    it is all weird. I'd expect BER be always some value. not 0 some time and then jump to over 1K for few seconds and go back to 0.
    also I'd expect that during the time there is BER, there would be drop in Signal, SAT quality or SNR. especially when same SAT dish, same LNB, same cable in the wall, same tuner, all worked fine with old LE8 on X86 box. I guess I'll reflash old box with new LE to see if it's HW or LE version/newer Sundtek driver/something else. and before I do that, I'll plug it again and check the mediaclient output there to see if BER was there either.

  • exactly as I thought. same sat dish, same lnb, same cable in the wall, same sundtek tuner, but old LE8 x86 box and literally 0 BER on the channel that was unwatchable on recent LE/CE HC4 box.
    so, it is either newer sundtek driver, newer LE/CE version (I tried both) or HW host issue.
    I'll reimage it with new LE version and if it works, then it's HC4 HW or sundtek driver. if it doesn't work, it's either LE/CE or sundtek driver.

  • I want to point out (again) that the colour distortions and green lines in the images in post #1 are due to the current Amlogic hardware video-decode driver. It is not in a good state. It generally works okay with older Amlogic hardware and less okay with newer. The driver is in staging and is effectively unmaintained for 2+ years, and it predates SM1/S905X3 hardware being released. There is also a dependency on the codec and version of firmware blobs being used (lots of variables).


    You should be aware that current LE (needed for some level of HC4 support) is running completely different kernel codebase and drivers to older harware running older LE images or CE which are using vendor kernels. The upstream kernel and vendor kernel drivers have zero in-common.

  • I want to point out (again) that the colour distortions and green lines in the images in post #1 are due to the current Amlogic hardware video-decode driver. It is not in a good state. It generally works okay with older Amlogic hardware and less okay with newer. The driver is in staging and is effectively unmaintained for 2+ years, and it predates SM1/S905X3 hardware being released. There is also a dependency on the codec and version of firmware blobs being used (lots of variables).


    You should be aware that current LE (needed for some level of HC4 support) is running completely different kernel codebase and drivers to older harware running older LE images or CE which are using vendor kernels. The upstream kernel and vendor kernel drivers have zero in-common.

    ok, I understand. so even if I re-flash my older x86 device with newest x86 LE, the test may not be relevant.
    I understand you're talking about that I may not get good image quality even if I resolve the "lagging" issue which turned out to be the random and unexpected BER reported by the sundtek driver as distorted image was only one part of the issue, another was lagging of the stream I got.
    but I stuck with LE8 for a reason. I had same issue with Leia (LE9) when I wanted to upgrade, TVHeadend wasn't able to tune any services from transponders and if I copied the configuration of TVHeadend server addon from LE8 to LE9, the stream was "lagging", so I'm just curious if it wasn't the same root cause.
    and correct me if I'm wrong, but I guess that the BER on sat stream has nothing to do with video driver, but of course it is dependent on kernel.

  • ok, I gave up. the HC4 won't be all-in-one solution (nas, kodi, tv streaming). it will be purely ubuntu NAS and kodi headless. perhaps I'll test docker based tvheadend there one day, if it works better.