Solved! Onboard audio interference

[ApacheSK]

Hi, I have some problems with onboard audio, some time ago i switched to a new PC case, that has malfunctioning front 3.5mm headphones jack (only right channel plays), I tried to use MIC In jack, and retask to Headphone/Front Speaker out, but somehow it still doesnt sound like real Headphones jack, but that's not what i'm writting about now.

So I've plugged headphones to the rear F.speaker-out (Green) 3.5mm jack, but there's some interference, i know i can't get crystal clear sound out of onboard audio (ALC 892), but when plugged in front panel, there's no interference, until I plug headphones to rear port. The interference is still here even when I mute sound (so it should be some interference out of cables behind PC?), and if i retask from "Front Speaker Out" to "Headphones" (I mean i turn on the motherboard built-in Headphones AMP), the interference is stronger.

I also tried another headphones (I used earbuds from my mobile phone - idk if it's good for testing presence of EMI) but there was no interference, tried both with AMP on and off, but still nothing.
Mine headphones are Audio-Technica M20X and Motherboard is AORUS B450 M, and some earbuds packed in with phone (honor).

Thanks for help.

 

[hang-the-9]

Since you have a bad front port, I would disconnect the case audio headers from the motherboard fully and see if the same issue is there.

You said this happens with only a single headphone set correct? Could simply be a connection issue with the headphones and the jack you are using. Try using a contact cleaner on them.

 

[ApacheSK]

Well I tested only two headphones (Audiotechnica and earbuds), but i'll try to clean it and disconnect the front panel, I hope it will be only some dust in connector

 

[ApacheSK]

So I disconnected front panel, and tried to clean the rear ports, but they are clean, also i tried Line-in retasked and it's doing the noise too. So I think it's only problem of Motherboard audio, the sound intensifies when I move the mouse (tried two more mouses plugged into front USB - same result).
And I tried to plug headphones into front Mic-in and put whole cable to the back of PC, but it pick no noise, so I don't know what could cause it... Especially I dont understand why there is no noise in earbuds when plugged in rear ports

 

[hang-the-9]

Test with another set of headphones on the port with the issue, a full headset, or speakers. So far you only know the earbuds work, and the headphones don't.

You can get a sound card for the system if the audio issue is there, or contact the motherboard vendor and work with their support.

External USB sound cards are great to remove any issues with interference in the case, for headphones without a mic, I like the FX Audio DAC6, good features and for the price it's a top choice.