Microphone plays all PC sounds

[tottyboi]

This issue started randomly, previously it didn't occur so it may be software.
However I did build my PC so possibly (a small possibility as it worked flawlessly prior to this incident) may be due to wiring.

Information that may be useful in narrowing down the issue:
- Changing where I plug in ports doesn't seem to change anything.
- Stereo mix isn't on.
- All other audio outputs/inputs are disabled.
- "Listen to this device" option is off.
- Changing Realtek options doesn't change anything, tried every combination (e.g Echo -
Cancellation, Noise Suppression etc.).
- Reinstalled drivers multiple times.
- Not microphone leakage as I have tested by physically muting the mic and the issue still occurs.

One other thing:
The issue isn't exclusive to programs, for example if I record my microphone with the microphone recording software on Windows 10, it will record background noise (no other programs open, other than ones that generate noise to test it, e.g Spotify/YouTube).
But it happens on Discord also but when the PC audio begins to play through my microphone and is more prominent, I can leave the call and join back which makes the effect much more mild and even negligible at some times; this happens every 5 - 30 minutes where I have to rejoin the call as it becomes too unbearable for people I'm speaking with.

Help would be greatly appreciated.

 

[tottyboi]

MERGED QUESTION
Question from tottyboi : "Microphone plays all PC sounds"

This issue started randomly, previously it didn't occur so it may be software.
However I did build my PC so possibly (a small possibility as it worked flawlessly prior to this incident) may be due to wiring.

Information that may be useful in narrowing down the issue:
- Changing where I plug in ports doesn't seem to change anything.
- Stereo mix isn't on.
- All other audio outputs/inputs are disabled.
- "Listen to this device" option is off.
- Changing Realtek options doesn't change anything, tried every combination (e.g Echo -
Cancellation, Noise Suppression etc.).
- Reinstalled drivers multiple times.
- Not microphone leakage as I have tested by physically muting the mic and the issue still occurs.

One other thing:
The issue isn't exclusive to programs, for example if I record my microphone with the microphone recording software on Windows 10, it will record background noise (no other programs open, other than ones that generate noise to test it, e.g Spotify/YouTube).
But it happens on Discord also but when the PC audio begins to play through my microphone and is more prominent, I can leave the call and join back which makes the effect much more mild and even negligible at some times; this happens every 5 - 30 minutes where I have to rejoin the call as it becomes too unbearable for people I'm speaking with.

Help would be greatly appreciated.