Sound randomly switching between TV speaker and soundbar

[zsc0re]

I have a Sony soundbar HT-X8500 and a Sony Android TV KD-49XG9005BU.  I have connected these via the eArc connection using HDMI. I purchased this HDMI cable https://www.amazon.co.uk/gp/product/B07KWNPZ1L

Now, the following happens frequently when viewing TV (either internet streams, cable etc.)
- the TV output continues to randomly switch between the TV Speaker and Audio System (soundbar).

I have no idea why this is happening.

Has anyone experienced this issue before please?

Thanks
Ben

[royabrown2]

@zsc0re 

If the cable is as good as the supplier’s English, that would explain it.

But what is happening is that the ARC handshake is coming and going; either because one or both devices aren’t keeping it up, or because the cable is faulty.

Try turning it round; try another cable; if both devices are eARC, try dropping to ARC; if one of the two only is eARC, try switching it explicitly to ARC.

Report back and we will go from there.

[Peter_S.]

Hi Ben,

I agree with @royabrown2 

You would need to use a cable that's compatible with HDMI 2.1 when using eARC.

Your cable is only compatible with HDMI 2.0.

Cheers

Peter

[royabrown2]

@Peter_S. 

Ah - so are we saying that eARC, even just with 4K, requires more than just the HDMI 2.0 with Ethernet which the cable referenced provides?

[Peter_S.]

@royabrown2 

Yes, I would say so since eARC had been introduced with HDMI 2.1.

Cheers

Peter

[royabrown2]

Thanks @Peter_S. 

A couple of observations, after looking at Sony’s specs for these devices:-
https://www.sony.co.uk/electronics/support/televisions-projectors-lcd-tvs-android-/kd-49xg9005/speci...
https://www.sony.co.uk/electronics/sound-bars/ht-x8500/specifications

(i) The TV is only shown as having ARC. Has it got eARC in an update, or is ARC only still the case?

(ii) Neither device is specified as being at a certain HDMI level. Perhaps there is more detail in the manuals, or other supplementary material, but how are users supposed to know that they need an HDMI 2.1 compliant cable?

About which I anyway remain deeply sceptical. It used to be that cable manufacturers were actually prohibited from using an HDMI version number when describing a cable, and the key thing was what speed they would support, and whether they were plus Ethernet or not.

(And according to the source I quote at bottom, they still are, and can’t put HDMI 2.1 on cable or packaging; though they can now allude in marketing material to supporting features in HDMI 2.1, like

Auto Low-Latency Mode (ALLM)
Variable Refresh Rate (VRR)
Quick Frame Transport (QFT)
Quick Media Switching (QMS)

But not eARC, as this is supposed to run over earlier cables.

And this is still the case, with HDMI 2.1 now being shorthand for a cable that will run at 48Gbps, rather than the older High Speed of 18Gbps, and will always have the Ethernet wire that is now used for eARC.

But what, in the user’s setup here, with not a sniff of very high refresh rate 4K, let alone 8K, might be demanding 48Gbps? Especially just for ARC, or even eARC.

Also:-

From: https://www.hdmi.org/manufacturer/hdmi_2_1/index.aspx)

Q: What cable(s) do I need to make use of the eARC feature?
A: Ultra High Speed HDMI Cables are designed to support the new eARC feature in addition to the highest resolution video modes. The Standard HDMI Cable with Ethernet and the High Speed HDMI Cable with Ethernet will also support eARC.

eARC

Q: Will this work with any HDMI cable?
A: This works with HDMI High Speed Cables with Ethernet and the new Ultra High Speed HDMI Cable.

Q: Is eARC available through a firmware upgrade?
A: Generally speaking, no. Check with the manufacturer of your product to confirm.

Q: What audio formats are supported?
A: The latest high-bitrate audio formats are supported including DTS Master, DTS:X, Dolby TrueHD, Dolby Atmos and more.

Q: Will the existing ARC-enabled products work with new products that use eARC?
A: Maybe. Manufacturers can produce products that are compatible with both eARC and ARC. However, eARC is not defined to be backwards compatible with ARC.

So maybe the OP’s mix of ARC and eARC is a problem, and the soundbar needs switching down to ARC?

[Peter_S.]

Hi royabrown,

Thanks a lot for all the details.

So a standard HDMI High Speed cable should work as well.

My thoughts on this issue were that the cable quality wasn't good enough. Then I spotted that the connection was done via eARC which obviously cannot be the case since it's not supported by the TV but the soundbar (see IM).

So guess I've headed into the wrong direction with the proposal to use a HDMI 2.1 cable.

Anyway, I think the cause of this issue is related to the cable quality OR (new suspect) it's because the soundbar is set to eARC which is not supported by the TV. So maybe turning off eARC in the soundbar would be worth a try.

Cheers

Peter

[royabrown2]

@Peter_S. @zsc0re 

Yes, we are on the same page again here., with the first option to try setting the soundbar down to ARC, and the second a new cable; even though the one he has should nominally be OK, a more established make (and not necessarily a dearer one) might work better.

But while the soundbar should detect the TV is ARC not eARC and drop to ARC only, the effect described could exactly be a soundbar failing to do that, but that keeps optimistically retrying for eARC.

[zsc0re]

First of all, thank you for all the replies and insight, this is incredibly helpful.  

I did not realise that I have plugged in the soundbar eArc to TV standard Arc.  Interestingly, I could not see a way to force ARC vs eARC on the soundbar (after looking at the manuals).   I've also been looking at the TV settings e.g. HDMI control.

I will also try a different HDMI cable.  Do you have any recommendations please? 

Thank you.  

[Win_88]

Interested to know where this goes! Do let us know.

Win_88