You would need the Cube USB hub (white little box) to bypass Apple's Lightening restrictions. Otherwise, iOS will pop up "device not supported". I'm enjoying Groove with Sennheiser IE-800 right now. Great combo!
New to WA5-LE are the following:High power 1/4” x 1 and 4-Pin XLR x 1 headphone outputs (up to 8watts)User selectable High Power or Low Power output via front panel switchesUser selectable High or Low impedance via front panel switchesUser selectable High or Low output LEVEL via front panel switchesXLR input x 1 These changes will benefit a wide variety of modern high-end headphones such as @MrSpeaker ETHER, @Hifiman HE-1000 and others coming to market.