I have some good news about the HD DAC:

The firmware has got an update in March (4.6.509530.45 / 20230302) and it doesn’t brick the device anymore, at least with the unit under review.
The 4stream app received as well an overhaul (3.1.18.230210) in February, and they included the 5Ghz network toggle that was missing and which was heavily criticized. Thumbs up for that!
 

The app itself still has a search engine on valium, but the app throughput i.e.  like Radio Paradise works quick and without hick-up.

Playing from local sources works without problems in the ultra-fast WIIM app. I would consider using 4stream only for the setup.
Setup works now with both, Ethernet and Wi-Fi, however using a double-push of the power button to enter the WIFI set-up mode has now found its way into the FAQ, which seems to be quite helpful.
Instruction:
When your Wi-Fi light is blinking to indicate the Wi-Fi connection is ready, it doesn’t connect (for setup) before you haven’t double pressed the power/select button. Done that, it’s the typical WIIM breeze setup.

I would connect via Wi-Fi only in case you are not happy with a Cat 5/6 cable tailing from the light little box.

Playing local files from the phone worked flawless up to the proposed 24-bit/192kHz.
Using DLNA/UPNP run into quality issues for both, with fix/wireless, at bandwidth higher than 24-bit/96kHz.

Overall this is a much better development for the device than I had expected when I wrote my rant pointing out the flaws.

Given this development I can at least recommend the unit for DIY projects.

Kudos to Arylic product engineering not giving up on that little device.

on a sidenote ...

WIIM PRO PLUS available in the US for command since Monday, August 5th.

Don’t forget to look at the all new  WIIM Pro plus, which offers a more complete package with a more recent and powerful Linkplay module in combination with a AKM4493SEQ DAC Chip.

Here’s a quote from te WIIM forum
“Better ADC + Better DAC + OPAMP

• Simple system – direct to your AMP or powered speaker without external DAC
• Upgraded DAC with OP AMP, redesigned power circuits and upgraded ADC that can do up to 24-bit/192 kHz.
• Audio quality comparable with WiiM Pro connected to the external DAC (up to $500 price?)
• Save the external DAC and cable cost
• Some low-end DACs don’t handle the clock, variable sample rate/bit depth properly, or don’t support up to 24-bit/192kHz digital input
• SNR: 120 dB (A-wt)
• THD+N (1 kHz): 0.0004% (-108 dB) for 44.1k to 192k
• FR curve: +/- 0.1 dB

It features a new generation AKM 4493SEQ premium DAC that is able to achieve a leading level of low distortion and wide dynamic range thanks to AKM’s Velvet Sound Technology.”