Question PC making weird buzzing noise after resuming from sleep mode

Apr 15, 2020
So this started happening about a month ago. When I turn my PC on, it's all fine. However, if I resume my PC from sleep mode after 20+ minutes of inactivity, my PC makes this weird buzzing noise that you can hear here. This happened about 5 times, and 2 times after clicking my mouse button to "wake up" my PC from sleep mode, my PC would start booting and then it would stop, only to start booting after a few seconds. That exact thing happened in this video here. My PC was asleep, I clicked the mouse button, it started booting, and then it just stopped, as if it died for a few seconds, only to resume after a few moments. I was on Windows 7 when this started happening, and now I'm on Windows 10, the issue obviously isn't software-related. I'm just not sure if it's a power supply issue or a hard drive issue, or a CPU issue. The sound seems to be coming from the front of the PC, and the only things that are in the front are my 2 HDDs and my power supply. My specs are:

Intel i5-4670K (stock fan)
ASRock PRO3 Z87 motherboard
Kingston HyperX 8 GB 1600 MHz RAM
2 GB of 1333 MHz RAM
ASUS GTX 1060 6 GB
HDD 500 GB Hitachi HDS5C1050CLA382
HDD 3 TB Seagate Barracuda ST3000DM001-1CH166

Here is the video (you might wanna turn your volume up):

I suspect this might be an HDD issue, though I'm not sure which one is causing the issue, and I'm not even sure if it's an HDD problem at all. I bought an external hard drive to back up my data just in case.