Perhaps, but even so, the FiiO X7 is supposed to have this capability and I'm sure there are times when it may be useful to some. I'm not sure if I would ever need the feature, but as I said, I thought this firmware update was supposed to make this functionality available.
I use my DX90 as USB DAC frequently, and it is great versatility to be able to listen from PC-storage using Foobar for music I've not yet transferred to DAP or SD card. I am hoepful DP-X1 will implement this soon, by time of US release when I anticipate finalizing a purchase decision.
It is confusing to me (perhaps reflecting my ignorance of Japanese language and reliance on google tranlation) that the release notes here indicate:
2016/1/29
[DAP Notice of software release (DP-X1) to your customers]
Of DP-X1, which I am patronize, we will release an updated software to 2016/2/3.
When you receive the notice of the update to your hand of the product, Please confirm the contents of the software update information, we would ask that you perform the update in accordance with the instructions on the screen.
This software is scheduled to improve the following.
And operation improvement of the SD card at the time of reproduction at the time of the operation stability and music playback stability improved user interface display bug improvement · USB DAC connection of the trouble improvement · DAP Music app · DAP Music add apps to FF / FR function ※ release It is scheduled for 2016/2/3.