So I got Apple and Samsung cables, quite possibly counterfeits, hard to tell.
The Apple didn't support anything above around 48kHz. So it's being returned.
But the Samsung has handled everything I've thrown at it, up to 384kHz. And more importantly it has changed my Salnotes 7hz Zero from sounding a bit muffled to really blowing me away.
Unfortunately I'm waiting on a audio out/mic splitter before I can do latency testing, as both the mic and the speakers have to be running off the same device for the tests to work.
UPDATE: Moved latency testing to new thread: viewtopic.php?f=29&t=1724