So i just built this new computer...
Immediately thinking you need to download and install the sound drivers from your motherboard manufacturer or the chip manufacturer.
Most integrated sound cards are very buggy. I'd get one that plugs into you PCIE x1 port. They are very cheap.
I would disagree with this statement. In 16 years of system building, I've never come across a motherboard where the on-board audio was faulty.