Blue Jeans Cables is a really reputable cable house. If they couldn’t make it work I doubt that I will either. Nevertheless, I’m going to try. I’ve located a breakout box and will make the proper connections.
I’ve followed your lead and also talked to Bluejeanscable and they confirmed what you said. I2s isn’t always I2s even though it should be. Different manufacturers’ I2s won’t necessarily talk to each other, even if cable pinouts are correct.
If it doesn’t work then all I can do is buy the D-D converter or switch to AES/EBU. Is there any quality loss in doing this? I was under the impression that iis was the most accurate connection.