This is gonna sound stupid & seem patronizing, but it's not meant to.
Are you actually plugging the headset into the headphone input? Cause I built a new system (without color coded inputs, yay) & not only did I initially reverse the sub/center channel & surrounds for the speaker outs, but the damn headphone & line-in jacks at the front of my new case were reversed! I plugged in headphones, they were stupidly low & had interference & <Mod Edit>, so I just plugged them into my speakers. Found out later that I was plugged into the Line-In instead of the headphone jack.
If that isn't the issue, my next suggestion is to make sure that your connections are all tight & that none of the wires are loose. Unplug the audio connector at the motherboard & make sure the pins are clean & not bent or broke off & that the leads are secure in the little plastic connector (a missing or loose pin-out can ruin your day) & make sure the connector properly aligns.
Looking at your mobo schematic, there will be a blank pin-space on the male connector on the mobo at the top row of pins, second to last from the rear of the board. Likewise, there will be a corresponding blank (no pin hole) slot on the plug at the end of the wire. It's sometimes possible to plug the Audio cable in upside down, despite being "Keyed." It looks to be labelled "JAUD1" & it's the bottom most interconnect on the board.
If none of that solves the problem, I would get a can of DeOxIt. WITH THE SYSTEM OFF & UNPLUGGED, use the straw to give the jacks a shot of DeOxIt, wait a second then work the connector in & out once to break up any deposits, remove the connector & give the inputs a final shot, after which you make your connections & put the DeOxIt away, giving it enough time to dissipate before firing the equipment up.<Mod Edit> works. It's a measured shot, so there's little chance of using too much. Just make sure you keep the straw inserted into the jack a little bit so it doesn't slip out & douche your system or your case or whatever.
Hope it helps & if it doesn't, I apologize. With no mention as to what your last mobo was, we don't know if the two PC's boards were running different audio codecs or what. FWIW, that board is outfitted with a Realtek® ALC892 Codec, which according to numerous reports, kinda sucks balls. My own ears agree with the assessment regarding the gargling of the danglers & would add that they might even belong to a monkey. Either way, I made sure to get a mobo with at least an ALC1220 Audio Codec and I'm glad I did. It's a noticeable improvement that sounds much better than the ALC892. It's not on the same level as having a dedicated sound card, but it's pretty damn good. Good luck, buddy.