I do want to point out that one of the reason why DX100 is able to do it is because they are doing it all in the software mode with essential an almost full feature ARM based CPU. Most SoC used in DAP doesn't have that much processing power so SoC manufacturer hardware coded all the coder onto the chip in effort to play certain format with the minimum available processing power. Since >16/48 is never that popular, most SoC simply doesn't support it in hardware - and without the kind of CPU like DX100 or dedicated firmware design, getting 24/96 and above is actually very difficult for the DAP maker, especially since most SoC supplier will see no benefit on their end to custom tune their firmware for only a handful of devices that are only ordered in small quantity. Thus the reason why iBasso takes the Android route as it is an open OS that they can take advantage of, as opposed to HifiMan which takes over 2 years to develop their own firmware in the upcoming HM901 to support 24/96 and above. A opposite example will be ColorFly's C3, which has a DAC that supports 24bit decoding but the Rockchip SoC they used isn't known to support 24bit format in most format so they ended up only support 24bit in wav but not the others.
As time goes by technology advances and expectations go up ClieOS. Not saying that it is an expectation that they support such a format but it sure would increase their customer base. Although the biggest things so far are hiss and UI which need to be addressed. Then of course if they can add support for Hi res files that would be awesome. One reason why I am kinda looking forward to the new iRiver player.