This may sound like I'm going crazy but bear with me... I recently stopped using my USB speakers and starting plugging headphones directly into my motherboard's audio output. It sounds fine for the most part aside for a little bit of static. However when I transfer files over the network or download, the static increases. Once the network activity stops, the sound dies down. I've started to now notice something similar with video too. If I do anything that causes the screen to refresh quickly (like scrolling down a page fast), the static gets much louder. I get this is obviously something to do with interference, but is there anything I can do to reduce it? Motherboard is an Asus P5W DH Deluxe using a Realtek HD audio chipset.
That, my friend, is called interference. VERY common for onboard sound cards. The ONLY fix is to get a dedicated sound card like the ASUS Xonar... great sound card, even the lowest end.
Exactly right there Goodbytes - onboard sound is terrible for interference, and is the main reason some manufacturers have started putting their "onboard" sound cards onto external add-in modules.
Using an optical audio cable running to a separate receiver also does the trick, and the only way i've ever been able to eliminate electrical noise completlely. Since it's headphones you're using, you could try one of these, or something similar but less violently expensive... http://www.techradar.com/reviews/au...dio/amplifiers/ibasso-d10-cobra-636659/review
For (higher end) headphones I'd recommend the Asus Xonar Essence STX/ST. Many poeple over at head-fi.org favor it over most headphone amps sub $400. If your headphones are cheaper grab something $20+, most will do you just fine.
