Question

Apple TV 4K + LG OLED55C7P + Playbar/etc. + Belkin Ultra High Speed HDMI Cables

  • 22 November 2017
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So I recently invested in the LG OLED55C7P, which is gorgeous. I can now run my individual HDMI sources (Cable, Apple TV 4K, Xbox One 😵 to the TV, and audio out through optical to the playbar and beyond. All was good for video and sound - 5.1 for each source, and I didn't need a splitter (I used the Octava before, with my old TV).

In reading about Dolby Vision, etc., I saw that Apple recommended the Belkin Ultra High Speed HDMI cable. I saw conflicting opinions, but I wanted to use the best that I could, so I bought the cable and stuck it between the Apple TV and the TV. Boom - I started getting the 'Unsupported Audio' error in Sonos. I recycled power for everything, tweaked the TV audio output settings, tweaked the Apple TV audio output settings, and no luck. So, I swapped the good old HDMI cable back in, and life is fine.

So my question is - does anyone have perspective on why this cable, which I'd assume would be backward compatible, would have issues? The TV (2017 model) can pass through Dolby Digital/DTS multichannel via Optical, and it works fine with the non-Belkin cable between the Apple TV and it. I'm still getting Dolby Vision via the Apple TV with the old cable, so I don't seem to have lost anything, but it didn't make sense to me, so I figured I'd ask the experts!

Thanks in advance for any thoughts.

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49 replies

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This is interesting, never heard anything like it before.
HDMI cables are now a nightmare as there are so many older versions out there.
Maybe ATMOS needs this new HDMI lead you bought, and the tv is now getting this signal and switching to a higher audio format that won't pass through optical.
I have read that my OLED B6v 2016 won't pass any higher audio format than DD5.1 & DTS through HDMI or optical, so there is no advantage between either type of lead out of tv.
I did once see DTS ex (or something like that) via optical on my sony AVR from a rented Blu-ray from PS4.
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Yeah, it's a little confusing. The 'upgraded' HDMI leads are clearly passing something more 'robust' to the TV, from an audio standpoint, that is then cascading into the optical feed to the Playbar which it can't interpret. Bummed to have wasted money on the Belkin cable, but at least things are working now.
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I picked up this cable today to try and resolve my issue getting 5.1 from my Nvidia Shield to my C7. Someone on Reddit said it fixed his 5.1 issues completely but now with what you are saying I’m unsure.

I run the shield via hdmi and the sonos through the TV’s optical. I am plagued with 5.1 issues. Sometimes it works and sometimes it just stops working. I have no idea and I can’t find a definitive resolution. For some people like you it seems to work and I just don’t understand. Any help would be appreciated.
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It's still not working consistently for me. When switching between my cable box, Xbox One X, and Apple TV 4k, I sometimes lose audio completely. I have to switch to the Xbox HDMI input (for whatever reason), and then back to the cable box or Apple TV 4K input. Something seems to get reset when I cycle through the Xbox input. Very odd. And obviously I can't take advantage of Atmos, because Sonos has decided to not support the standard, unfortunately.
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So your 5.1 is intermittent across different hdmi inputs?

Mine will work for a while then just stop and I get silence. Like you say, I have to mess around with the inputs to get it back.

Maybe this is a TV issue and LG need to patch it. It’s just strange because some people say it works and others don’t. I’ve read seen anyone who has the issue find a fix.

I do run my other devices desire to via Optical to an optical splitter box and they work perfectly. Unfortunately my Nvidia Shield (Like the Apple TV) doesn’t have an optical port. I have tried HDMI audio extractors with no success and was hoping this new HDMI cable would work as someone on reddit said it did for him.
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Yep, it's either 5.1 or nothing for me. Once I have it for a given input, it works fine. But it's shaky when switching between inputs. I'm usually able to get it to work by switching through the Xbox input and then over to my final destination.

LG did release 4.70.30 of the firmware recently. I had to download and install it via USB, it didn't show up via 'Check for Updates' yet.

I've had a lot of success with the Octava switch in the past, and may go back to it. I was just hoping to eliminate it from the 'supply chain' between the TV, Sonos and the devices.
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Yeah I got the firmware update installed also. The problem with the Octava switch is that it doesn’t fully support all the 4K/HDR/10bit/Rec2020 in order to pass the video untouched and split the audio.

I’m baffled as to why LG has not fixed this yet. Apparently it’s been an issue since last years model. It seems limited to HDMI to Optical passthrough scenarios where the TV can’t handle it, yet it should be able to.

If the Nvidia Shield / Apple TV had an optical out we wouldn’t have this issue. At least we’ve narrowed it down to a TV issue. Took me a lot of time and reading to get to this point.

A guaranteed fix is buying a receiver that’s capable of passing through everything. Expensive though. Not found any HDMI audio extractors/splitters that can do the full job.

I will update you as to how I get on with the Belkin HDMI cable tomorrow. Luckily I brought it from Apple and can just return if no good.
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Thank you, yeah, that's part of why I wanted to skip the Octava also. I'd hoped that the 2017 LG would handle it, but d'oh. Yes, please do let me know how it goes!
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Just a quick one. I exhausted all the splitter available on Amazon UK. I found this one on Amazon US which may tick all the boxes.

https://www.amazon.com/J-Tech-Digital-Extractor-Converter-Bandwidth/dp/B074HHSJVN
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But won't that consume your Playbar optical input for only your Nvidia? Do you not have anything else running up to your TV that was going back down optical to the playbar?
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I have an optical splitter that works great. You can switch the optical in use by using an IR remote or Harmony Hub in my case.

The HDMI audio extractors would grant me the Nvidia Shield optical audio. Problem is that one I have linked is not sold in the UK. The ones I have tried from UK store all fall short in one area or another. Either they don’t support full HDR or have issues splitting audio
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Ah, ok, gotcha. Mind sharing the optical splitter model?
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Portta 4 Port 4x1 SPDIF/Toslink Digital Optical Audio Switch/Switcher with IR Remote https://www.amazon.co.uk/dp/B01A89OEUY/ref=cm_sw_r_cp_api_UQIgAbQHE5DG4

That’s the UK link. I’m sure you’ll find one on US store. Are you gonna try the J-Tech one I linked? Worth a go and just return as not working if it doesn’t.
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Nice - thank you, I'm going to give both a shot. I appreciate it.
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No problem. Let me know. Likewise tomorrow when I get the cable.
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Will do. Order complete, should arrive Tuesday.
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https://www.monoprice.com/product?p_id=24278

Here’s another one which looks very similar to the jtech one you have ordered. Look at the review, seems promising.
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Okay, so I got my Belkin Ultra High Speed cable plugged from the Nvidia Shield to the TV with the Optical then from the TV into the Sonos via the optical splitter. So far so good. Working as my original cable does but so far no drop outs...

I will keep using it for tonight and tomorrow and see if I get a drop out. If I do, then we know it’s not a fix. If it turns out to be a fix for me and as someone on reddit said for him, I would be interested to see what’s going wrong on your side. But I will keep you posted.

Regarding the HDMI audio extractors. Let me know if it works for you. Problem I have found is that my Nvidia Shield needs a specific HDMI setting which must be passed through said extractor.

3840x2160, 59.940 Hz, YUV 420, 10-bit Rec. 2020

I’m not sure if the HDMI extractor I linked you supports that. The second one from Monoprice definitely doesn’t. But as the J-tech one is similar looking, I expect the same. It may or may not be an issue for you but I’m unsure how the Apple TV has its HDMI setting.

I did find another HDMI extractor from a UK website which claims it supports YUV 420 10-bit but no mention of 2020. Here is the link:

https://www.lindy.co.uk/audio-video-c2/hdmi-2-0-18g-audio-extractor-embedder-p10050

Will report back soon with updates.
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Okay so it dropped out. Cable is 100% not a fix. HDMI audio extractors are the last hope.
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Ok - fingers crossed for you. I'll let you know how it goes with first extractor. Focusing on the picture today - spending the morning looking for a good calibration service also, I want someone to come out for a visit soon. Running the compensation cycle 'slides' at the moment.
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Oh shoot, just saw your second post, that stinks. Extractor time then.
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If you haven’t already, check out this for good picture settings.

http://www.rtings.com/tv/reviews/lg/c7-oled/settings

I may order the £100 extractor I linked above as it may be my only option.
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Yeah I based mine on those as a good starting point. I've been scouring the AVS forums also. With each firmware upgrade, they need to get tweaked it seems. I really need a professional I think - the TV is too good to not get that touch I think.
I’m having the same exact problem, same setup...looking forward to your next update
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I’m having the same exact problem, same setup...looking forward to your next update

Do you have Apple TV or Nvidia Shield? Not that it matters. Me and ChadB should have our extractors tomorrow and we’ll update the thread.