Beam (Gen 2) disorted / metallic sound w/ TV (eARC) and Night Sound Mode

I’ve not used SndUp before, but I have uploaded a recording of what I hear from the Beam when playing the start of that YT TJATOMICA Superman video, which I just recorded using iPad Pro mic - here is the link (hope it works)…

http://sndup.net/p3fs

(extract from beginning until Superman takes off/launches).

I don’t hear a metallic sound but maybe it’s a frequency I’m not noticing. See if you hear it.

It’s probably not the best recording but at least shows what I’m listening/hearing here, which seems fine and ties in with what I hear when it’s played on the iPad too.

Hi Ken,

i have also recorded what I hear on my Beam. Note that this recording was done in direct proximity to the sidewards pointing speakers in the beam, not in the middle of the room.

Thus the effect is very clearly audible.

find it here:

http://sndup.net/rvwz

First ten seconds - no night sound. Then after 10s, nightsound enabled - which in this case seems to not make that much of a difference.

It shows as „Dolby Multichannel PCM 2.0“ in the Sonos app.

Pretty akward that your beam reports a different audio format playing back the same video.

Looking at the original Video Stats, it seems audio is „Opus 251“ which translates into being stereo (2channel) VBR.

Also, can you confirm you directly connect the TV to Beam, 1:1 with the Beam HDMI cable?

Cheers,

Kai

@Ken_Griffiths 
P.S.: I cannot hear any distortion in your recording. Maybe worth doing the recording in direct proximity to the sidewards pointing speakers again.

The recording via  the iPad Pro was done directly in the middle of the beam about 6 inches away from the front of it.. but will listen out again to the side speakers.

• PCM stereo format to the Arc was from the LG TV’s own built in YouTube App and that TV is directly connected to the Arc (eARC connection)
• The Dolby Digital Plus 2.0 to the Beam was from a Nvidia Shield via Feintech VAX04101A extractor which I use with that TV but the Beam uses eARC connection to that extractor too - so maybe that’s the reason for the differences in codec. (Sorry it’s the best I can do with each of the HT setups I have here, without moving the devices about, which would be a lot of hassle for me).

Maybe others here will chime in and perhaps help test this on their HT setup too, but not hearing the metallic sound so far here.

Just as a thought - Maybe it’s the codec on the sending device that’s the cause of the issue here and not the Beam hardware, perhaps 🤔?

It might help to play the same audio, using the same codec, to a different speaker, if practicable, to see if it sounds the same. I assume this only happens with a few sources rather than it being a widespread issue. Something to do with some sounds and how they are being transcoded before being sent to the Beam?

Just wondering if maybe we’re looking in the wrong place as to the cause of the issue, just because the sound is coming from the Beam, it may not be the speaker, but something happening before it gets to the speaker in the transcoding stage of the audio itself?

Can anyone else here perhaps say if this only happens whilst listening to the audio in Dolby Multichannel PCM 2.0 format, as that might help narrow things down to that codec and/or the sending device… (that’s assuming the TV is set to pass-through the audio uninterrupted)?

@Ken_Griffiths 

“maybe its the codec on the device sending”:

yes, maybe. But on the other hand, we have peope reporting it on Sony TV / Virgin V6 Box [1] and myself I had it on a Pansonic TV (which unfortunately I have no access to anymore).

So I would like to second your thought, someone who can reproduce audio as “Dolby Multichannel PCM 2.0“ would be extremely helpful.

I understand that connecting the Beam to LG directly to reproduce is not currently possible for you, Ken, correct?

[1]

https://www.avforums.com/threads/beam-gen-2-disorted-metallic-sound-w-tv-earc.2429996/#post-30935186

@Shnakey 

Can you help us out here:

1. does the error on your end sounds similar to what I recorded (see above)?
2. what is your TV model?
3. What is the Sonos App showing as the audio format, at the time you reproduce the error?
4. if you had an LG tv, is the error also going away if you disable pass-through and switch to PCM?

Cheers!

Yes, I can connect the Beam direct to the TV, I guess, as the TV does have an HDMI-ARC port, but not eARC, that’s the reason I got the Feintech extractor to allow me to play Atmos and uncompressed Multichannel audio, as the built-in TV Apps sadly only support (upto) Dolby Digital 5.1.

My Sonos Arc is directly connected to my main TV (LG C9 OLED) over HDMI-eARC and I will keep trying to see if I can get the metallic sound to show up on there too.

I will test with the Beam directly connected to the older LG TV (2015), (but it won’t get uncompressed Multichannel PCM over HDMI-ARC, as the codec is eARC only) but will see what I can discover from that setup too.

So is the current thinking, that it ‘might’ be connected to the Multichannel PCM codec? … as I do also have an Apple TV 4HD that uses Multichannel PCM, albeit that’s connected via the C9 TV and the Sonos Arc?

Anyhow, I will keep trying and report back if I hear anything.

Some further audio sample/suggestions might perhaps help here too.