help! Can someone help me with my broken audio port

[rocketbagel]

My motherboard, the gigabyte z370 aorus gaming wifi rev 1.0, has an integrated sound processor and bundled software that would allow me to have a 5.1 surround setup if it works. However, one of the female 3.5mm audio ports just doesnt output properly. It is the C/sub port and all sound is extremely muffled and sounds like this. i have cleaned the port out once already with compressed air and it made no difference. I have tested the speakers and they all work fine, it is just the port. I really hope that this is a problem that i can fix myself. Thank you for your time!

The port: https://imgur.com/a/8nBRhE5

the mobo page: https://www.gigabyte.com/us/Motherboard/Z370-AORUS-GAMING-WIFI-rev-10/support#support-dl

[rocketbagel]

Also i have to switch the sound software between headphone mode and 5.1 mode everytime i start up my pc for any audio to play...... but thats a problem for another day

 

[suedseefrucht]

We see 5 3.5 mm audio ports here.
Top right is an input for a microphone. Don't use it. Nothing should come out here.
Top center is stereo for both of your front speakers.
Bottom right is for your center speaker or subwoofer.

Bottom center is for both of your rear speakers (stereo).

Bottom left is just a headset output. Not for 5.1. Don't use it.

 

If you have a nice audio receiver it should have an optical input.
You could just get an optical cable and connect your motherboard's optical out to your audio receiver and you would have perfect 5.1 with just 1 cable.