HDMI modulator fails to send sound over coaxial cables to peripheral TVs

Forums › Freeview (DVB-T/DVB-S) › HDMI modulator fails to send sound over coaxial cables to peripheral TVs

Podgebro

7 posts

Wannabe Geek

#315976 4-Sep-2024 11:10

Recently I had my Sky box "upgraded " to the new white sky box connecting it to the main TV in the lounge. This actually went smoothly and successfully. I had a technician come in and replace the old RCA modulator which supplied to the 3 other TVs in the house - and this had always worked well.

When he was here the transition to an HDMI modulator supplied very good [720p50hz] images to the other TVs but created only audio noise on these peripheral TVs. Modulator is a Proquip.

This was resolved by him replacing my old 55" Sony Bravia in the lounge, with one of my newer TVs [Panasonic TH-50AS640Z] and sound and images were good. It was suggested that a brand new TV would resolve all issues.

After he left and we turned off the main TV that night and retired, all the other TVs had good images but no sound.

Sound and images are good but only if the main TV is left on.

Does anyone know how we can attain sound on the other TVS without having to leave the main lounge TV on?

Would buying a brand new TV really resolve the issue?

Spyware

3761 posts

Uber Geek

Lifetime subscriber

#3278767 4-Sep-2024 11:31

Should be Sky decoder to HDMI splitter with one output to main TV and other output to DVB-T modulator. Do you have an HDMI splitter? or does modulator have HDMI passthrough to main TV??

Spark Max Fibre using Mikrotik CCR1009-8G-1S-1S+, CRS125-24G-1S, Unifi UAP, U6-Pro, UAP-AC-M-Pro, Apple TV 4K (2022), Apple TV 4K (2017), iPad Air 1st gen, iPad Air 4th gen, iPhone 13, SkyNZ3151 (the white box). If it doesn't move then it's data cabled.

skewt

750 posts

Ultimate Geek

#3278772 4-Sep-2024 11:52

He hasn't configured something correctly

For starters, you should be getting better than 720p50hz

As long as a TV is 'Freeview Capable' you do not need a new TV, he just hasn't configured the modulator correctly. certain TV models are fussy if you use the incorrect settings but most of that relates to trying to get LCN's working and Id Assume hes left you on 'Channel 800' or similar

As for the sound. Ive seen it disappear when HDCP isnt working correctly on a modulator
The modulator in questions appears to offer a 'pass-through' HDMI signal so when the TV is on it might be handshaking the HDCP protection and fixing the audio, This can usually be bypassed on the modulator itself

Podgebro

7 posts

Wannabe Geek

#3278921 4-Sep-2024 16:02

Spyware:

Should be Sky decoder to HDMI splitter with one output to main TV and other output to DVB-T modulator. Do you have an HDMI splitter? or does modulator have HDMI passthrough to main TV??

Thank you for replying. There is no HDMI splitter. The first HDMI cable goes from the modulator[HD in] to the sky box; second HDMI cable [HD out ] goes to lounge TV then the coaxial cable to the peripheral TVs comes off the modulator[RF out].

So I guess HDMI passthrough to main TV?

This coaxial cable goes to 2 or 3 other splitters in the house.

The dish coaxial cable of course, goes to the sky box.

Podgebro

7 posts

Wannabe Geek

#3278930 4-Sep-2024 16:09

Podgebro:

Spyware:

Should be Sky decoder to HDMI splitter with one output to main TV and other output to DVB-T modulator. Do you have an HDMI splitter? or does modulator have HDMI passthrough to main TV??

Thank you for replying. There is no HDMI splitter. The first HDMI cable goes from the modulator[HD in] to the sky box; second HDMI cable [HD out ] goes to lounge TV then the coaxial cable to the peripheral TVs comes off the modulator[RF out].

So I guess HDMI passthrough to main TV?

This coaxial cable goes to 2 or 3 other splitters in the house.

The dish coaxial cable of course, goes to the sky box.

Channel 251 for what its worth. He may have tried 1080p -I don't know- and possibly found that the setup couldn't manage it. Not sure how to change anything on the modulator.

He originally used it out of the box, and when we could only achieve static noise on the other TVs he swapped the modulator for another one[same brand and model] and then he substituted the lounge TV to accomplish the current situation

Podgebro

7 posts

Wannabe Geek

#3278991 4-Sep-2024 17:29

Sorry modulator is set to Channel 42.

Should I look at a HDMI splitter then?

richms

28168 posts

Uber Geek

Trusted

Lifetime subscriber

#3279048 4-Sep-2024 18:48

I would check the sky box is outputting 2 channel pcm and not a bitstream option as who knows what the box is presenting as an edid or if if just passing the tv one thru.

I no longer have access to a sky box easily to know where on the menus that would be.

Richard rich.ms

skewt

750 posts

Ultimate Geek

#3279064 4-Sep-2024 20:15

Do you have no audio on all sky channels when this is happening?

Try the trackside channels (62,63) as they have less protection to try pin point where the issue is

Another thing to try
Power off sky/modulator and power it back on without the HDMI pass through going to closest tv.. do you get audio then?

If possible, try take some photos of the menus on the modulator.. a lot are similar so we might be able to see something that might solve it

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Podgebro

7 posts

Wannabe Geek

#3279263 5-Sep-2024 12:52

Thank you all again. To answer queries:

1.I cant see in the sky box settings whether it is set to pcn or bitstream

2.No audio on all sky channels ; trackside channels give same result

3. Interestingly, if the lounge TV is disconnected and the HDMI modulator is powered off and then restarted, as you suggested, everything works well on the peripheral TVs- at 1080p [changed freq on modulator as I think it was set to 720p by default].

If the main TV is then reconnected everything still stays working properly-normal image and sound.

This trick does not work if my dear old [2010] Sony Bravia 55" digital TV is reconnected.

4. Modulator menu options photo-failed to upload but options are:
Display Status
Setup Modulator
Channel Information
Define User Channel
System Config

skewt

750 posts

Ultimate Geek

#3279397 5-Sep-2024 21:52

Could go through all the modulator settings but easiest fix might be to go buy a cheap HDMI splitter and place that between the modulator and sky then link to the tv from there

Grab a splitter that’s under $20 since these ones usually strip out HDCP
https://a.aliexpress.com/_mOCFz6g
I’ve been using these $12 ones at work between sky + modulators but any cheap one should be fine

Podgebro

7 posts

Wannabe Geek

#3279507 6-Sep-2024 11:39

Thank you Ultimate Geek. I'll give it a go and let you know how it goes.

Podgebro

7 posts

Wannabe Geek

#3283967 19-Sep-2024 10:28

Update: Resolved! I got a cheap HDMI splitter as you suggested- from Temu[1 input/2 output] but it took 9 days to arrive.

Have set it up and it has completely resolved the problem. All peripheral TVs receive good picture and sound regardless of whether the lounge TV is on or off, making me very happy. Even my old Sony Bravia is fine.

Ever grateful for your advice and guidance on this, especially not having to buy a new TV - which wouldn't have helped anyway.

Thank you so much one again!