Lightning Headphones with a splitter? I got these great-sounding new Fidelio M2L/27 Lightning Headphones that take the digital signal through the lightning connector and then use the high-quality DAC in the headphones themselves so I can listen hi-fi audio from my iPhone 8. However, I am also a mobile app developer and hence I need to also often connect my phone to my computer to debug. I bought a cheap lightning splitter (1 male lightning to 2 female lightning) on Amazon and it doesn't work with the earphones - even if that's the only thing plugged in. 

1) Is this an issue with the splitter not being MFI certified? Will my headphones not work if they are the only things plugged in?

2) If I do get an MFi certified adapter will I be able to use the headphones and have the data connection to the computer at the same time? Do lightning connectors allow two data connections at once?
I looked up a couple of splitters including one from Belkin and another cheap one from Amazon. Neither splitter supports data transfer at all, through either port.

I'd hazard a guess that this isn't possible. At least I haven't been able to find a device that explicitly states that it does support data.