I use the Razer Tiamat 7.1 heaset with mine and I have to have Flexbass [ON] to get the appropriate bass response when "in-game." I changed my sample rate to PCM 192KHz for best quality. But so far I like most of the default settings. I do miss the "Party" equalizer setting from my old on-board sound card because it emphasized the Highs and Lows without losing the Mids. I've tried to replicate it on this sound card's EQ but the sound always gets distorted and fuzzy. It seems that I get the best quality from preset EQ settings but I don't like any of the pre-sets on this card. I don't know if i'm just used to my old setup but when I changed my settings, I immediately fell in love with them. I have not been able to find that setup yet with this sound card. I have tried to change many of the other settings but most of them I do not notice a difference so I revert back to the default settings to keep things simple. One thing I do notice is that when I turn [HF] on I lose all bass. I also do not see a difference with the [GX] mode. I run my headset in 7.1 mode because they are a true 7.1 headset meaning that have 5 individual drivers(speakers) in each can. It's a great headset, it has its ups and downs though and I would only recommend it to someone with a dedicated sound card. Even if your mobo has a 7.1 built-in sound adapter, you will not get adequate results. One major issue I had with my on-board sound adapter was that it was feeding coil whine from my CPU to my headset which led me to buying this sound card which did fix my issue. Many people stated the buzzing issue was a USB grounding issue and that connecting to a AC to USB wall adapter would fix it. After later diagnostics I noticed the pitch of the buzzing to change when my CPU was under different loads and resorting to blaming coil whine for the buzzing in the headset.
So all in all, I have found the Default settings to be perfectly fine because I do not notice any difference in games or music when tempering with the major settings. If anyone knows anymore about this card and could explain the differences in settings I believe everyone, especially the OP would love to understand a little more about this card, including me.