Laptop beeps while Windows 10 in sleep mode and HDMI cable plugged into KVM switch

[StooBush]

I've got a weird one for you folks. I've got a brand-new 15-ec1073dx. I upgraded the RAM with a matching 8 GB stick and added a 500GB SATA HDD. I didn't really use the system before the upgrade, but since I did it, when Win10-64 goes to sleep, and an HDMI cable is connecting the laptop to my 2-port KVM switch, the computer beeps incessantly. If the computer is plugged directly into my monitor via HDMI, the beeping doesn't occur. If the HDMI cable is connected to nothing, the beeping doesn't occur.

I reseated the RAM and HDD cable. I've run HP Diagnostics UEFI and everything passed, so I think my upgrades are good. I've not tried just removing them and seeing what happens, but that's likely next on the list, in case there's some sort of ground loop.

HP tech support wasn't helpful, though this is such an odd duck, I'm not surprised. I really just want to know what the beep means. It's incessant, which is why I suspect a ground loop, but I've got no way to confirm it. Maybe it's the KVM switch (I tried reversing the ports and disconnecting the USB inputs to no avail....the issue recurs whether or not the KVM switch is connected to a monitor). Maybe it's something inside the Pavilion.

Thanks in advance for any help.

-S

[StooBush]

Okay this is just getting weirder and weirder. I replaced the SATA HDD with a SATA SSD, and that stopped the beeping, but now when the HDMI cable is attached and plugged into the KVM switch, when the computer goes into sleep mode it no longer recognizes the SSD.

Not sure what there is to do at this point except to disable sleep mode and just live with it. Or ditch the KVM switch for a different one, I suppose.

-S