Yes, the motherboard is a Gigabyte GA-970A-UD3 and it came with a disk that contained many drivers
including a VIA HD audio driver
. The sound problem was the same before and after installing the audio driver and I couldn't find any settings in the VIA HD audio deck that remedied the problem. I even tried uninstalling the VIA HD driver and reinstalling it but that didn't seem change anything.
If it helps, before the hardware change and sysprep, the old pc was using a realtek audio driver. After I changed the hardware like the motherboard and CPU and used sysprep to keep my Windows 7 installation, the realtek audio dirver icon showed up in the 'uninstall programs' menu in the control panel and I double clicked on it and uninstalled it from there. Hopefully that completely removed all the realtek components but I'm not 100% sure if the realtek drivers are completely gone. I mean, it doesn't show up in the device manager under 'Sound, video and game controllers' so I assume it's gone but I'm still not completely sure.