Hullo. I am having some terrible sound quality issues (extreme muffling across whole range, differing based on whats being listened to), here is the need to know. So I have recently experienced using Beyer DT 990 250 Ohm Pro, V Moda Crossfade LP2, and now currently Senn HD6 Mix (and an old pair of $30 Philips just for good sample size). I have used them all off my new computer which has a Z370 AORUS Gaming 7 mobo, and this is listed as using the following "121dB SNR AMP-UP Audio with RealTek ALC1220 & High-End ESS SABRE 9018 DAC with WIMA audio capacitors" and advertised as providing "a pure yet powerful sound". The problem in quality is that certain music/genres/songs sound extremely bad (IE: muffled) relative to others, and I have played with the on board windows equalizer presets on everything I find issue with (basically everything). Some tracks and video games sound less muffled typically around the soft and powerful presets. I have to replay every troubled song over and over just to find an exact preset that makes it sound less muffled and not like I'm hearing it on cheap garbage, but even then? It still doesn't sound good, and even leaves an audio impression that there is a band aid over a deeper issue. When it comes to video games it becomes the worst. Every game I try sounds worse than the worst sounding music with this issue. Muffle evolves from one room away to two away and under a few blankets. If games present a source option I have already ensured that it is not on surround. Attempting to equalize the games is fool hardy, the equalizer accomplishes even less with them and the cover up sound becomes even more apparent when fiddled with (messy, distorted, and while sounding less worse, it also still sounds far away from natural). Basically, it sounds like something is very wrong with a software setting or hardware itself that I can't determine, and no amount of equalizer can cover it up (my best way of defining "band-aided" sound). Only solution so far, when I plug into my tiny cheap old logitech speakers, I don't even need the equalizer as much. While I can hear the hiss in silence and the reduction in overall quality, the over all muffle almost disappears, the lows, the mids, the highs, all of it brightens and sounds like the sound is in my room and not the room over. I'm hoping you can educate me on why cheap speakers would unmuffle HD6s much less any of the headphones I've used. Is it some impedance interaction thing I don't understand? Does plugging into my speakers possibly bypass either an incorrect audio setting or something else in the hardware? And let me clarify, after extensive googling I have already verified that all audio enhancements, aside from the equalizer setting I use, are off on every audio device, and that I made sure that all devices were configured for stereo and not in surround which I know is a culprit for many people. The strange thing? This is exactly what the muffle issue sounds like, the muffle sounds like surround sound is on screwing with everything but extra bad than it normally does. I cannot find much detailed and accurate talk about audio experiences with different mobos to even come up with an answer on my own. I couldn't find anything resembling my issue at all particularly about all video game sound being even more muffled than other audio. My biggest fear is that this is a bad mobo for audiophile sound quality even though it's advertised as such.