Just nitpicking but can't leave it be: DAC stands for Digital Analog Converter, and there's going to be one involved everywhere data is converted into pressure waves, ie audio you can hear.
But yes all "enhancement" (apart from maybe just plain old EQ, if needed to get flat response from not-so-great headphones, but depending on how the EQ is actually implemented it might cause weird side effects, also: do not "leave it flat", turn it off completely, see note1) is going to mess up the binaural sound designed to work with plain stereo output.
I see no reason why a stereo headset with built-in USB DAC would not work just fine as long as it's plain stereo without anything "enhancing" the signal and the headset analog side is of reasonable quality.
That said, I don't understand why anyone would actually want a fully integrated USB setup (apart from the RGB LED control bling, but I never understood that either). a decent quality stereo+mic DAC is not expensive or big and you don't need any drivers since it's an audio device as defined by the USB standard, everything supports those out-of-the-box. Then you can plug in whatever headset you happen to like or even separate headphones and microphone. Maybe it's because sales/marketing -people can make one want all kinds of things that on closer inspection are not all that desirable.
Also regarding "enhancing": HiFi stands for High Fidelity, where fidelity means faithful(nes). Faithfully reproducing the sound as it was recorded (or intended to be reproduced if generated on the fly) any "enhancement" of the sound goes completely against this principle.
note1: because in "flat" it's still doing the time-domain to frequency-domain and back to time-domain conversions even if it's not doing any changes when in frequency domain, but this goes a bit deep into theory.
Just confirming that it's not a problem with "USB DAC" in general, it's something else related to this particular headset, which has more "features" than just stereo out, mic in.
If I had to guess the "virtual surround" driver messes things up, it being "disabled" doesn't neccessarily mean a thing unless it can be completely uninstalled. Also possible that the headset just has a weird physical configuration that has been designed for optimal performance with the "virtual surround" system and completely messes up binaural stereo, in which case there's very little the devs can do about it (basically they can only start fully supporting the "virtual surround" thing but that's not a small effort, especially since there's bound to be subtle differences between drivers).
If it's the driver, unless the game somehow can tell the driver to stop playing silly buggers with the stereo sound the game is playing (it's not like the game uses any sort of direct access to the sound hardware, it all goes through the windows sound api) there's again very little the devs can realistically do about it.
Though if the observers are not helping the commander then the commander can simply switch classes, it's not like it's "a better class" in any way when they can't use supports and team is not any worse off because they were not going to get that support anyway. Maybe someone else will step up and manages to convince the observers to be better team players.
The commander doing the "wrong things" and not taking instruction or stepping down is more of a problem for the team.
And yeah, definitely gotten my share of salt from people who run right under my supports even though I always announce them in voice and often even before actually calling the support tell the team to slow down a bit because I intend to call supports before we go to the point.
I play commander most of the time because no-one else seems to want to and I see the value of having those supports... "It's a shitty job, but someone gotta do it"
edit: I also generally play with a few friends in a group so I almost always have a "trustworthy" observer, they take one observer first then I'll see if anyone else is willing to play commander. if not I'll step up, if yes good for them, they have a good observer.
I use the Asus Xonar U3 as plain stereo DAC (and ADC for the microphone, headset is fully analog) and it works fine. Never used any "virtual surround" systems, they just confuse things when properly designed binaural stereo works just fine.
I don't watch movies on my computer, I have a proper 7.1 soundsystem and projector for that, so I have no use for a driver that pretends to be multiple actual stereo channels and maps to binaural stereo. And of course one would hope that the sound designers for the movie mixed the plain old stereo soundtrack properly too and in that case the virtual driver probably leads to poorer results.
If the commander is doing "stupid things" because they haven't yet figured everything out they can usually take instruction, use the voice chat (because reading the text chat when things are hectic is not really going to happen). And be polite, it will help so much in getting your message understood when the receiving end doesn't think you're just being an asshole.
Ditto for the observer being reminded that they need to stay within quick sprinting range of the commander unless the commander is being a total idiot and not taking the instruction given.
General votekick will solve the most troublesome cases.
The softer version would be allowing rest of the team "mutiny" on the commander and the commander to "relieve of duty" an observer. Both forcing them to change class (default to rifleman, can choose new one as usual) at next resupply/respawn as usual. Not sure if actually worth the development effort though, maybe if NWI is stuck on never allowing general votekick again then this could work to soften some of the frustration of poor commanders and solo observers.
"Observers capture faster" is IMO a very, very poor reason to play observer as "high speed, low drag -operator". I didn't even know that actually being a thing. A much better mechanic would be to have the observer and commander together capture faster (than other classes, so extra bonus for being a good team) but if not in range for support then have the standard capture speed.
Let's start by stating the fact that everything can be abused by the trolls (and damage reflection is being abused) so saying that X can be abused is in no way a proper argument against it.
Now, if standard votekick where the vote can be initiated anytime by anyone is "too easy to abuse" (I personally never have seen it abused) then maybe allow votekick only on teamkill (or major team damage). Though sometimes I so hope for votekick when some asshat is spamming the voice and being general pain in the backside (how about that in-game "report player" feature).
Votekick on tk is kinda like the "forgive" system but with more teammates taking part in the discussion.
Docking XP points for team damage could also be an idea (and showing it in big red letters in the post match report), just to have people think about what they're shooting at a bit more. Make the penalty large enough and make it possible to actually lose XP and levels and maybe the trolls start thinking twice about it as well (especially if matchmaking takes this into account somehow).
There are real-world tactical shooting competitions where shooting clean is way more important than completing a stage quickly (even though shortest total time wins the match) and the penalties for hitting a no-shoot (or not neutralizing a target) are scaled accordingly, like 60 seconds per penalty which totally destroys any perceived advantage of "being quick".
Remember kids: slow is smooth, smooth is fast.
I've said it elsewhere too but let's add my 2cents here as well.
Damage reflect is a piss-poor way of discouraging team-killing and I have never in any game personally seen vote-kicking being abused (we all hear the same FUD-stories about it being abused and certainly it's possible, but who has actually seen it being abused at all, let alone in amounts that would outweigh it's utility ??)
It's not like there's not a whole bunch of other ways for griefers and trolls to piss people off.
When playing with high-speed-low-drag ultra-operators this can generally be blamed on them not bothering to clear the path but I've seen this happen also when people are being careful and trusting that slow-is-smooth-smooth-is-fast is better approach.