Microphone doesn't work when HDMI out is in use (and enabled)

Hello. I have a problem. A problem I did not have up until a month ago or so. I have a TV screen plugged in as a monitor. However, after some time, about a month ago, microphone stopped working.

At first I've thought microphone went just bust (it's a cheap $5 one and I had it for over 3 years), so I've plugged it in into friend's laptop to check it. Nope, worked there. Keep in mind that at this point I've used my TV as computer screen for over 3 months with no issues whatsoever all the time plugged via HDMI with audio working fine, it will be important soon why.

Next thing was to update sound drivers to newest Realtek ones. Nope, didn't help. So I went googling. Somewhere I've read that HDMI output may conflict with microphone. But it worked good up to this point. Weird. I've decided it's worth to try and disable HDMI out anyway just to see.

Lo and behold, microphone works after disabling HDMI audio. But wait a minute, it worked before without disabling HDMI audio, so what the hell?

Anyone knows any real fix for that issue? You know, any that doesn't involve disabling HDMI audio each time I want to record something? Like it was the case before this started to happen? And without buying any extra hardware, please.

Except I want to record my microphone, not whatever is playing in Winamp.

Nope, it already is. As I said, it works when I disable HDMI audio playback device connected to my TV, but disabling it each time is cumbersome, especially since I record often (I'm both a game developer and need to record some samples for my game like all the time and on top of that I'm a podcaster + there's also a YT video from time to time).

I've already did everything from the "are you sure it's not ID10T error?" checklist, including reinstalling audio drivers (as stated in OP). I've been using computers since I was eight, was programming since I was 10, now I'm 25 so it's been quite some time I've been using those aside of gaming and office suites. I'm also a Linux power user and administrator and the only reason I have to use Windows now is because of one specific software (Unity Editor) I need for work is only available for Windows and OSX, soon to be rectified though (and then I'll be able to return to the land of Glorious Penguin!).

So excuse me, but I really know what I'm doing and if there would be obvious solution to my problem that would return recording to normal, I'd done it already. I'm looking for less obvious things, one that I've might not considered.

Still need the help.