I have a soundmax onboard chip and it doesn't play well with RoF. Over the front I had single digit FPS, plugging in a USB headset (to use different drivers/hardware) fixed it completely.
Someone else here had a similar issue with a Realtek onboard chip. I'd check your drivers and if possible take it out of the loop somehow to see if it's causing the problem. A driver update fixed the realtek, there are no recent drivers for the soundmax.
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