No audio over cat 6a cables

No audio over cat 6a cables

Author
Discussion

kashn

Original Poster:

194 posts

203 months

Wednesday 21st December 2022
quotequote all
Asking on home cinema forum to get better responses:

We had a Loxone smart home system fitted nearly 4 years ago and a blustream 8x8 HDBaseT matrix. This sends HD sky and firestick and cctv images to all the rooms along with the relevant audio.

now


Now looking to add a dedicated room to use as a cinema room with an Optoma projector and sapphire screen.






Signal from the Blustream is decided using the blustream receiver:


But:
The picture is fine but we can’t get any audio.
Tried changing the receiver bases, the source, a tv instead of the projector, and cable is obviously ok as wouldn’t get picture otherwise. Have recrimped the cables too just incase.

Now I’m stuck for an explanation and not sure to try next.
Any ideas guys?

MrSparks

651 posts

127 months

Wednesday 21st December 2022
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The matrix doesn’t support ARC (audio return channel) so this won’t work.

You’d need to get a different extender set from Bluestream that does support ARC to send the TV audio back.

Not 100% sure that you’d be able to pipe that into the matrix though so this might be a standalone solution.

I used a Bluestream extender set for this recently, they aren’t cheap and we only had one TV so no matrix to worry about. Worked perfectly.

VEX

5,256 posts

253 months

Wednesday 21st December 2022
quotequote all
Have you ruled out a faulty BlueStream receiver, by using a kniw good onw that works in a current (preferably low use) room.

Was there anything on that cat6 run before hand?

What is the model number of the Bluestream matrix? Some early matrix generations could switch audio and video independently.

Other than that even i am a bit stumped at the moment. I don't think its an ARC problem as they way you have described it all sources are in the central rack.

I am assuming audio is good in other rooms?

What are you using for audio playback in the new cinema room? Is there an Amp / AVR / Processor in the chain?

V.

OldGermanHeaps

4,216 posts

185 months

Thursday 22nd December 2022
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What edid are you using for the audio, do you have surround in all the orher rooms?

kashn

Original Poster:

194 posts

203 months

Thursday 22nd December 2022
quotequote all
So we are not using an audio system, just straight forward TVs. The sound appears to be fine to my ears through the tv speakers.
When using the same tv and same base receiver in the cinema room, picture is normal but no sound.

The model of blustream I’m using:

VEX

5,256 posts

253 months

Thursday 22nd December 2022
quotequote all
So are you expecting to have sound from the projector?

It may be the the edid from the projector isnot requesting audio, i have had it before when matrixes only learn edid once when turned on or first connected.

So it may be that.

Where are you in the country? One of us may be able to visit and support.


kashn

Original Poster:

194 posts

203 months

Thursday 22nd December 2022
quotequote all
I’m in Edgbaston Birmingham.
When I connect to the projector, it makes a horrible knocking type noise and when i connect to the tv, there’s no sound at all
🤷🏽‍♂️

OldGermanHeaps

4,216 posts

185 months

Thursday 22nd December 2022
quotequote all
Have you tried swapping the cinema room output cable from the back of the matrix with a known good room?
Do you have the admin password for the matrix to check the audio settings?
If you are really stuck I could teamviewer in for a quick look.
Maybe the rack is sad because it looks untidy, a wee makover to pretty it up a bit would put it in a better mood?

Edited by OldGermanHeaps on Thursday 22 December 22:02

megaphone

10,940 posts

258 months

Saturday 24th December 2022
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What source? Sky HD? Check the audio settings on the box. Try rebooting the Sky HD box. Reboot the matrix.

Captain_Morgan

1,254 posts

66 months

Saturday 24th December 2022
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As I said on your other thread, these don’t encapsulate the av to ip, it uses the multiple twisted pair to carry the av signals.

So is perfectly possible for the pair(‘s) carrying video to have continuity while those carrying audio have a issue, hence the suggestion to do some speed testing over that cat6 run to confirm it’s state.

Again if you have used a known good hdmi input & output port on the matrix with a known good receiver on the suspect cat6 run it would (to me) point to the cable run being at fault.

OldGermanHeaps

4,216 posts

185 months

Saturday 24th December 2022
quotequote all
Why not buy a 20m premade cat6 patch lead and use that to narrow down the diagnosis?
Although I'm pretty sure the audio and video are multiplexed on hdbaset, its more likely you would see sparklies and purple artifacts than just no audio on a cable fault. Do you have the pairs wired correctly?
Sparks are the worlds worst for thinking cat cabling just has to have the same polarity at either end which will pass a continuity set but fail a verification test.
As far as blustream goes i use their uhd hdmi over ip multicast product, not their matrixes, for hdbaset matrixes i use hdanywhere, is there maybe a setting that the audio is going to the seperate audio output on the rx instead of going out on the hdmi cable?
Did you try using one of the known good outputs to feed the cable going to the cinema room?
Could you recap on exactly what all has been tried so far on 1 post?

Edited by OldGermanHeaps on Saturday 24th December 19:49

VEX

5,256 posts

253 months

Sunday 1st January 2023
quotequote all
Just a sudden thought.

Does the lrojector have speakers and volume options
Are they turned on in the menu
Does it work on a direct HDMI connection.

HNY

V.