HDMI Cables - CEC working but no sound or video

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aaristotle

145 posts

Master Geek

#205919 2-Dec-2016 16:08

I've spent the last two days running cables through the ceiling and walls, installing the TV, amp and speakers so all the cables are hidden and the TV is wall mounted away from the amplifier.

I finally connected everything, turned it all on and find the the HDMI connection from the TV to the AMP only transmits CEC info ie I can change the volume setting on the amp with the TV remote but no sound or video goes to the amp from the TV.

The HDMI cable in the wall is a 10 metre "DYNAMIX 10M HDMI 2.0 High Speed Cable with Ethernet. ULTRA HD 4K. 2160p 4K2K 60fps" cable connected via PDL faceplate connectors, then some old 1m (v1.3 or 1.4?) HDMI Cables from the wall to the TV and wall to the amplifier.

I tested the 10m cable between the amp and TV for a few days before installing and everything worked perfectly.

Is it possible mixing different HDMI versions in a cable run could be causing this problem? Or could the extra 2m of the wall to tv/amp cables push the HDMI distance limitations to far?

RunningMan

8965 posts

Uber Geek

#1681383 2-Dec-2016 16:44

The extra couple of metres could be enough - 10m on a passive cable is probably about as far as you'd want to go.

Got any better quality 1M cables to try at each end?

aaristotle

145 posts

Master Geek

#1681392 2-Dec-2016 16:53

I don't have any other cables but I will get two more 1m v2.0 HDMI cables of the same spec as the one in the wall.

If distance is more likely to be the issue I could get a 0.5m cable for the amp end and shave off half a metre of the overall distance, and if that doesn't work I could remove the PDL HDMI modules and bring the cable directly out of the wall to the TV and amp.

Brunzy

2016 posts

Uber Geek

Trusted

#1681394 2-Dec-2016 16:55

aaristotle

145 posts

Master Geek

#1681398 2-Dec-2016 17:08

Sorry, I forgot to mention the TV audio is using the HDMI ARC function to send the sound from the TV back into the amp. In the other direction a Bluray player attached to the amp should be able to be viewed and heard on the TV through the HDMI cable but this is not working either.

Masterpiece

247 posts

Master Geek

#1681412 2-Dec-2016 17:37

Note here that looking up the Dynamix site I find that 18Gbps (C_HDMI20-20) cables are active types, single direction.

Firstly did you connect the correct end to the display?
The cable type is directional.

I'm not sure you can connect an active type to a wall plate then to the amp and or display.
You should use a pass through cover plate(s) and directly connect the HDMI to the AMP and display.

Another problem, even with actives, Length of cable; it has been suggested to me by a device developer that that the way the newer HDMI 2.0(x) chipsets work means shorter than 2m cables can have issues with passing data.
The issue is related to the data envelop that the chipsets push.

I would strongly suggest the lower spec shorter cables are not adequate and you need active cables between devices and the amp, then active type from the amp to the display.

Me:"I'm not a robot!"

ET: "Maybe; you have some freewill, but you chose your path by arrangement"

Me "That sounds like a program with no freewill?"

ET: "We will catch up when you end this cycle"

Me: "Sounds like a 'KPI'!"

ET: "Did you read the terms and conditions?"

Me: .....

RunningMan

8965 posts

Uber Geek

#1681418 2-Dec-2016 17:45

Masterpiece:

Note here that looking up the Dynamix site I find that 18Gbps (C_HDMI20-20) cables are active types, single direction.

OP is using a 10m cable, not the 20m active one

D.W

726 posts

Ultimate Geek

#1681419 2-Dec-2016 17:46

Masterpiece:

Note here that looking up the Dynamix site I find that 18Gbps (C_HDMI20-20) cables are active types, single direction.

I believe only the 20M is active.

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chevrolux

4962 posts

Uber Geek
Inactive user

#1681420 2-Dec-2016 17:47

I have cheap Dynamix 15m HDMI cables that work perfectly (and I wasnt gentle running them in either haha). I would be looking at your PDL connectors. Are the in such a way you could connect the dynamix cable directly to the amp/tv. Assuming the PDL wall plates are just female/female connectors could be something dodgy there?

Masterpiece

247 posts

Master Geek

#1681429 2-Dec-2016 18:07

If not active, well i'd be surprised if they can do 18Gbps, anywhoo

Rough guide for Gbps

3840*2160 @24 8bit 4:4:4 = 8.91Gbps
(most high speed HDMI rated at 10.2 Gbps will work...maybe.)

3840*2160 @50/60 8bit 4:4:4 = 17.82Gps

Try a lower setting, see if you get a signal at 1080p24 8bit then work you way up the settings

Me:"I'm not a robot!"

ET: "Maybe; you have some freewill, but you chose your path by arrangement"

Me "That sounds like a program with no freewill?"

ET: "We will catch up when you end this cycle"

Me: "Sounds like a 'KPI'!"

ET: "Did you read the terms and conditions?"

Me: .....

Dunnersfella

4086 posts

Uber Geek

#1681633 3-Dec-2016 11:18

Lose the wall plates all together.

While you're there, install a coax cable... then buy an optical over coaxial solution for when ARC goes wrong... and yes, I suspect with your installation, HDMI CEC will go wrong.

Or, as most people recommend, go HD-BaseT (one that comes with ARC and optical return).

While you're at it, run a Cat cable for data.

richms

28218 posts

Uber Geek

Trusted

Lifetime subscriber

#1681638 3-Dec-2016 11:25

I have had wall plate passthru hdmi things that have been complete crap on their own, even with 2 short cables caused sparkles or nothing to happen. I suspect that inside between the 2 sockets they are just a very basic design without any care for keeping the impedance correct or anything like that.

Richard rich.ms

aaristotle

145 posts

Master Geek

#1686538 12-Dec-2016 13:34

An update on the HDMI cabling, I purchased two 1m v2.0 HDMI cables with the same specs as the original 10m Dynamix cable, and everything is now working correctly. This includes the PDL HDMI wall plates, the ARC audio, and Bluray videos in full HD.