Xonar SE soundcard audio stutters (WIN10 1809 vs 1903)

I recently got myself a Xonar SE sound card and have some trouble with it, or more likely, Windows 10, not sure which is the problem. Note: it has a C-Media USB2.0 6620A chip on it...so that means an ASMedia usb controller is tossed into the mix. Using the default MS driver or the ASMedia one included (but not installed by default) in the sound card driver package made no difference.

The problems:

1. Optical output cuts off the first 1-2 seconds of EVERY audio stream it plays. Short Windows sounds, for example only play the trailing end of the sound or are not even heard at all. So a "kabliiiiiiiing" sound is just "iing", and "biiing" is not even heard at all. Apparently this is a common thing for digital output, but I've never had it happen before with many previous sound cards. This little workaround fixes it it, but I'd rather not run some extra EXE to 'fix' something that should not happen at all.

2. Analog output has short dropouts/hiccups/stutters every few minutes or so, or anytime there is any activity on the PC. This was bad on Win10 1809, and is less severe/gone on 1903. No idea why but the onboard realtek and my usb headset never do this on the exact same build.

I want to run Windows 10 LTSC 2019 (1809) but the stutter/audio dropout is too severe. It seems fine in 1903, but yeah...I just installed it as a test, I can not stomach the M$ bloat in regular versions of Windows 10.

So my question is what changed from 1809 to 1903 that could cause/fix this problem? I'd like to solve it in LTSC 1809 and move back to that.

Info:
Windows 10 1809 or 1903, clean, new install with no extra junk, no virus scanners, nothing 'starting with windows', etc. etc.
AMD Ryzen 3 2200g @ stock speed
Corsair Vengeance LPX (CMK16GX4M2C3000C15S), 16GB (2x8), DDR4 PC4-24000 @ 2933
MSI B450 Gaming Plus
Geforce GTX 1060 3GB

I have tried different PCIe slots, bit rates, output ports (front panel vs rear) and all I've found is that Windows 1809 stutters badly, Windows 1903 does not.

Edit: more crap that does not fix it...
bcdedit /set useplatformclock true
bcdedit /set tscsyncpolicy Enhanced
bcdedit /set disabledynamictick yes
realtek energy efficient ethernet disabled

Edit #2: Windows LTSB 2016 (1607) seems to work fine too. So I'll just stick with that. I like it better than LTSC 2019 anyway.

Edit #3: Got a new ASRock B450 Gaming K4 motherboard, and Ryzen 5 2600. On this board problem #2 analog audio stutter is gone, even on LTSC 1809. Joy! Maybe the USB (Xonar SE has ASMedia USB controller) or PCIe slots on the MSI board were a little wonky...no idea.

Thought I would update this with the "results" in case anyone lands here from a search...

Well, after a month of back and forth with Asus 'support', here is their solution for the two different receivers (Yamaha and Sony) I have available...

Asus: "Please be advised that Optical out cut is because there will be some noise when start output in some situation to, so we mute about 0.x second.
We suggest if you want to connect to Yamaha RX-V375, you can use HDMI."

Cool, so buy a bunch of HDMI cables and use my Video Card for audio and have no monitor display unless my receiver is on to pass it through.
IE: don't use the Asus Xonar SE I just bought.

Asus: "If you want to connect SONY STR-DE945, you can use analog output or use your Realtek optical output.
And about the driver reset when boot, it should be only happen he close the sleep of win10 (the default shut down is hibernate ) Did you close the sleep in power option? Xonar SE use the same connect for Headphone/speaker , and default is Headphone.
If your win10 sleep when shutdown, the driver will not detect again, the setting will be the same.
If your win10 does not sleep when shutdown, the driver will detect every boot."

I do a full shut down without sleep or hibernate. The driver resets to things that are not even connected (SPDIF/Headphones, or my other USB Headphone) rather than what is connected "Speakers".
Solution? Use onboard Realtek optical (does not exist on my board) audio or the Xonar SE analog and listen to the stuttering, dropout mess all day.
IE: don't use the Asus Xonar SE I just bought.

Wow. Just wow. That's like Chevy telling me to just drive my 1972 Ford Pinto because the brand new Chevy Camaro I just bought needs a recall. So all I can say is avoid those Asus sound cards like the plague if you are researching buying one. The goal was to use digital/optical out, but I'm back to my onboard Realtek Audio via analog output and it works perfectly...for what it is.