Yes, the signal is shown correctly and the status is shown as Sync for SP op.

I have now for example clocking set to Auto (also could send it to SPDIF), so that Apollo is master clock. If I have sampe rate set at 96kHz and set it to 88kHz even during playback, everything works perfectly, once I set it to 48kHz and 44.1 Genelecs LED goes red and I started getting stuttered noises.

But yes, the status in the State Overview keeps changing correctly as I switch the sample rates and is clock supposedly always in sync according to the status in State Overview.

And the problem is obviously with digital output of RME ADI-2 Pro, because when I insert headphones into PH 3/4 they play perfectly, when the while Genelecs reject the AES with these lower sample rates.

Yes, UAD has no AES input nor output, that's why I was using this Hosa digital converter - to convert SPDIF to AES for Genelecs. I thought to use ADI-2 Pro for the same reason with extra benefit of giving me hi-end AD-DA as well.

Yes, I have absolutely no other digital input apart from SPDIF optical-in. No AES, no SPDIF and no USB.

I haven't tried any other cable to the Genelecs, but since this particular cable worked all the time and still works with Hosa and also works with RME ADI-2 Pro when I use sample rates above 48kHz, I really don't have a clue how could it affect the performance. I could also try to connect SPDIF optical out from RME to Hosa, but unfortunately have no other toslink cable in studio right now. But I find it redundant to purchase on Monday an additional cable to find such a partial solution (in case it works) because I really wanted to use ADI-2 Pro for this task.

Since headphones output work flawlessly at any sample rate while the Genelecs reject the signal, it really must be something related to AES out...I admit I am out of idea since I spent the whole day trying to figure it out.

For test I also recorded a SPDIF loopback with UAD.. recorded source was SPDIF-in with UAD that was received from SPDIF out of ADI-2 and sent to ADI-2  from UAD SPDIF-out and it also worked with any sample rates, while I couldn't monitor this procedure with Genelecs when at 44.1 and 48kHz.

I just tried it, made just one way connection UAD Apollo SPDIF out -> RME ADI SPDIF-in -> RME ADI SPDIF-out -> Hosa SPDIF to AES converter -> Genelecs, and it works like a charm. Even though that there is no reverse connection (loop), ADI successfully syncs with Apollo and everything works with all sample rates. As soon as I remove Hosa out of the chain and go UAD Apollo SPDIF-out -> RME SPDIF-in -> RME AES-out -> Genelecs everything is again like I described - Genelecs don't decode AES from ADI when it is 44.1 or 48kHz and start stuttering with the red led turned on.

It obviously looks something is wrong with my particular unit? Should I ask for a replacement? I would really like to use and can I expect that with a normally oprerating unit this should work without any issue?

I also just connected it via USB and forced it to rewrite the firmware once again, but nothing changed.

Ok, will try it now. So I set up ADI as an interface on my mac, set the CC-Mode to multichannel and go AES to Genelecs...will report it in 10 minutes. Thanks.

You missed the loopback test?

Tried it, while it had to record music that was streaming from Tidal, it only recorded a bunch of clicks and pops. I also saved the audio file in case there would be interest in examing it.

I set in Cubase 9.5 my ADI as my interface, set in6 and in6 as my input bus within Audio Connections and played Tidal in the background which was routed via outs 5 and 6 in my Audio-MIDI settings. I made a loop without inserting my cable because the cables on the breakout box from ADI are long enough so I could connect both AES XLR-s together.

Yesterday I had an additional thorough testing day.

First I tried according to your advice to connect AES in - AES out and listen to the signal via Phones 3/4 (source set to AES in) like you suggested. Using my cable nothing went through at salmpe rates 44.1 and 48kHz but everything worked at higher, if I connected directly the plugs breakout box without additional cable everything passed successfuly at all sample rates.

After that I used my three addional AES cables and non of them passed with ADI-2 Pro (I use the first going from interface to Genelec sub 7370, second from sub to one 8351 speaker and third from one speaker to another 8351 speaker). After that I borrowed form a colleagues studio another 4 AES cables (all different brands: mine were Klotz, he had two Mogamis and one Sommer cable). All of the cables are dedicated AES3 110Ohm cables and all worked with Genelecs and Hosa, but non of them worked with ADI-2 Pro.

After that I also tried them with my live recording rig that I brought from our rehearsal place, where I still use Fireface 800 and all the cables also successfuly worked with FF800 AES out. So there definitely must be something strange regarding AES output on my particular ADI-2 Pro, because it didn't let the AES signal at lower sample rates with any other cable apart from direct breakout box patching.

All of the cables were between 3m and 5m long which is nothing significant for AES transmissoion. All had Neutrik connectors.

So I am taking my ADI-2 Pro today to the store for a replacement, because I suppose if also Fireface 800 works with any of the cables I tested, there must obviously be something wrong with this ADI and it would not be normal for it to be so fussy about cables.

And I would like to thank you for your kind support and guidance...even though it was a weekend time. I really appreciate it and am very thankful. I am really glad to be a RME user.