Thanks, I can't easily check the main analog outs as all the wiring here is for digital, but listening simultaneously via headphone out on the ADI-2 it all sounds fine. I would expect the main analog outs to be the same (no audible issues).

The issue seems to only be on the digital outs and the Genelecs are being very picky about irregularities in the signal by dropping and flashing their lights.

One other thing, how are you controlling volume to the 8361s?

Connect ADI´s analog feed (Main Out 1/2 or Phones 3/4) also to Genelec, in parallel with digital.

Select analog input from GLM as source, or optionally mute ADI´s digital out (then Genelec switches to its analog input automatically), when listening TV.

Depending, are you having GLM running during use or not, defines which ADI´s analog out suits better your purposes. Using Phones 3/4 as analog output eases mute toggling from ADI´s side between its active digital and analog out, in case you are not running GLM in backround, i.e. doing that analog/digital switching from Genelecs side.

Genelec doesn´t switch automatically to its analog input if it senses digital input being active. Hence either digital mute from ADI´s side or you switching input manually from GLM side is required this to work.

One (1) more line cable run to speakers and pressing ADI´s volume knob to toggle mute / change GLM group is too much of an addition to all this audio nerd mega-setting you already have?
Really? Lol...

All you would lost in this approach, would be your audio nerd Pure Digital Pride™ when watching TV. Solution: don´t tell anyone in ASR...

Well, you could run the "usual suspects" i.e. test with another optical cable, if it would be the culprit to bad optical transfer... quite a little chance though. And TV´s digital out -related audio settings (if any) have been tested throughout?

You also already tried that SPDIF clock decoupling with setting ADI´s SRC to on, and it didn´t help either?

Only option left, which comes to mind then, would be to change TV to more reliable model.
I remember one similar case, in which LG OLED TV´s optical output caused problems to digital Genelecs, the fixing solution was change TV to Panasonic OLED TV.

I think this is going into the wrong direction. The first thing to check is the connection ADI AES Out to Genelec In. Different cable, breakout mounted correctly...

SRC is the next best suggestion. It will allow to run the ADI on internal clock, so there is no way for the Genelecs to show AES signal error caused by whatsoever ADI input signal. Unless the path AES Out to In is bad.

Mathias, how is the digital output volume handled by the ADI-2 Pro?  On our $500k SSL recording console, which is all digital, they opted to have D/A just before the analogue volume control feeding the studio monitors, mainly to keep the full 32-bit signal to the final output.  Their D/A conversion is so clean, it's not a step-down at all.  I feel the same taking analogue out of my ADI-2 Pro feeding my Genelecs at home... great D/A conversion and no compromises!

Just wondering?

FYI lock is not sync! It should display sync all the time. If I read your post wrong, sorry

Are you sure the red LED is AES transmission error? Not some protection (DC) or too high level peaks (might be in inaudible frequencies when coming from a TV...) kicking in?

You don't have another SPDIF source (CD player)?

Reading through the linked document it seems that there‘s something fundamentally wrong with the TV‘s optical output that renders it useless.

If I get the document right, beyond the dropout problem the audio quality of LG’s optical out additionally is largely compromised by harmonic distortions and noise bursts.

So, in every regard, using the TV sets analog outs into ADI-2 Pro would not only solve the dropouts, but improved audio quality too!

Is the error LED flashing on both speakers ?
Is the speaker very hot on the backside ?
Sure the speaker is standing free not covered with a deko cloth ?
Sorting out overheating.

Thank you, Matthias. I was puzzled about this (had read over the manual on SRC several times). I had wrongly assumed that use of the internal clock was somehow implied if the SRC option was selected. Thank you for spotting my error.

However, the difficulty I have is that on the Clock setting page I cannot change the clock to INT or change sample rates -- these menu options are greyed out. The unit is set in DAC mode. I can select these options if I change the unit to AD/DA mode, but then I lose the ability to easily switch between USB and SPDIF sources. Do you have any advice on how to best handle this?

BTW, does setting SRC do anything if the clock is not also set to INT?

Great, thank you KaiS and Matthias!

I can confirm that now -- with the ADI-2 in AD/DA mode, clock set INT, SRC on -- the errors completely disappear. As Matthias indicated, the ADI-2 takes what is an absolute dog's dinner of digital audio produced by the LG TV and produces error-free signal over its AES output. Sounds great and no more drop outs.

Thank you everyone for helping to debug this for me (it was user error, as usual). I'll try the "setup" trick to make this easier to switch sources -- thank you KaiS.

Now I just have to work out how to stop my USB source defaulting to a sample rate of 768 kHz when it is not playing. This gets used as the SRC sample rate for SPDIF input, and it's too high for the Genelecs to read (they accept max 192kHz).

Setting the unit into Multichannel mode limits the highest sample rate to 192 kHz.