Also interested about E10K pairing with X1. Keep us updated! Pitty it doesn`t have line-in/amp only function otherwise would get it for my DX50 to test and for work PC.
And sorry if my recommendation of Aune X1 didn`t work out for You but I said that I haven`t listened it myself and my recommendation came based on other impressions found on internet. Of course audio stuff is subjective and what may work for one person, might not suit to other.