I just received a Wiim Ultra today. I had canceled my previous order, but decided to go ahead and get one for my office setup. I'm glad I did.
I still wish it had a coax input, but I came up with a solution for that.
I'm using the Ultra as a pre-amp, streamer, dac and headphone amp with line outs going to a single Fosi ZA3 amp with output to Sony SSCS5 speakers. A Sony SACS9 subwoofer is connected to the Ultra's sub out. Connected a blu-ray player to the optical in for playing CDs and a USB SSD drive with my ripped CD collection. A PC, a chromebox, Fire TV stick and a 4k blu-ray player are connected to an HDMI kvm switch going to a Samsung 4k monitor. HDMI arc output from the monitor goes into the HDMI input on the Ultra.
Amazon, Tidal and Qobuz streaming and playing from the USB SSD drive all work as expected.
Everything is working great except for one bug:
When headphone output is selected, the Ultra cuts off the regular line output as it should, but it is still sending output to the subwoofer. Not sure if that is a software or hardware design issue.
I've listened to the headphone output with my HD800S and the Chu 2 iems. More than enough power for the HD800s at output level 48 out of 100. 33 was a good level for the Chu 2. The headphone jack is 3.5mm. I wish they had a 1/4" jack instead or in addition to the small one.