Did you try non-amplified headphones? If those work the noise is finding it's way though that USB power jack.
Bob
Please help.
My configuration is
i5 4690k
Asus Sabretooth Mark 2
Corsair RAM - 16 GB
Kingston 120 GB SSD
Corsair 650 VS SMPS
My UPS is APC 1100 RS.
Speakers are Quantum brand.
If I browse something or Hard disk is working the sound comes from speakers. I have checked speakers on laptop there they work fine. I have given power supply through another socket yet the sound is there. My UPS is also new.
I ahve tried an external sound card too. My speakers are USB powered. as soon as I insert it into USB it begins creating humming sound and when I browse something or play something processing sound starts coming from speakers.
I have now run out of ideas.

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