I just picked up a pair of M50s and realized quickly that my headphone jack 3.5mm on my Antec 1200 case has feedback when using the headphones. I think this is just because it might not be a quality jack, which is understandable. The motherboard onboard sound card works fine, there is no feedback. However, it seems that the volume cannot be nearly as high when using the motherboard jack.
My question is, what would cause this issue?