# Quad Cortex Static Noise without guitar cable plugged in **URL:** \ **Category:** Quad Cortex\ **Tags:** quad-cortex\ **Created:** [July 16, 2023, 6:48am UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463 "2023-07-16T06:48:15Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Ic3Ang3l](https://avatars.discourse-cdn.com/v4/letter/i/65b543/32.png) [@Ic3Ang3l](https://unity.neuraldsp.com/u/Ic3Ang3l)\ **Post date:** [July 16, 2023, 6:48am UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/1 "2023-07-16T06:48:15Z")
Hello guys, I just got my Quad Cortex and getting some terrible static noise. I am plugged in via xlr to my audio interface (the gain there is 0) and it doesnt matter if its an clean amp or high gain amp, the noise is the same. It is happening with and without the guitar cabe plugged in and only goes away when I select the input to “not in use”. I tried every input option and it doesnt matter, it wont go away. I already tried different AC sockets but since it is connected via xlr its no ground noise. Here is the noise; > **[QC noise.wav](https://drive.google.com/file/d/1m_mjN9Vp4v93lLCcM0xd84AaVxfRn_XH/view?usp=drive_link)** > > Google Drive file. ---
**Author:** ![MP\_Mod](https://avatars.discourse-cdn.com/v4/letter/m/ccd318/32.png) [@MP\_Mod](https://unity.neuraldsp.com/u/MP_Mod)\ **Post date:** [July 16, 2023, 8:57pm UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/2 "2023-07-16T20:57:29Z")
I would assume it’s something to do with gain staging from running QC interface into another audio interface. Try using just the QC as your interface etc. ---
**Author:** ![Ic3Ang3l](https://avatars.discourse-cdn.com/v4/letter/i/65b543/32.png) [@Ic3Ang3l](https://unity.neuraldsp.com/u/Ic3Ang3l)\ **Post date:** [July 16, 2023, 9:18pm UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/3 "2023-07-16T21:18:51Z")
Already tried that, doesnt fix the problem. The problem is still there with not guitar cable plugged in. With every selectable input. I guess its the preamp that has a high noise level. Even if it would be gain staging from qc set to -20!!! Db and the interface with 0 gain. It would be unusable live. ---
**Author:** ![MP\_Mod](https://avatars.discourse-cdn.com/v4/letter/m/ccd318/32.png) [@MP\_Mod](https://unity.neuraldsp.com/u/MP_Mod)\ **Post date:** [July 17, 2023, 4:13pm UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/4 "2023-07-17T16:13:10Z")
Also, using a compressor can have those results depending on how it’s configured. ---
**Author:** ![Ic3Ang3l](https://avatars.discourse-cdn.com/v4/letter/i/65b543/32.png) [@Ic3Ang3l](https://unity.neuraldsp.com/u/Ic3Ang3l)\ **Post date:** [July 17, 2023, 4:24pm UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/5 "2023-07-17T16:24:45Z")
Again, there is nothing in the signal chain. No comp. No amp. Nothing. The noise is still there. ---
**Author:** ![MP\_Mod](https://avatars.discourse-cdn.com/v4/letter/m/ccd318/32.png) [@MP\_Mod](https://unity.neuraldsp.com/u/MP_Mod)\ **Post date:** [July 17, 2023, 4:54pm UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/6 "2023-07-17T16:54:22Z")
Aside from emailing [support@neuraldsp.com](mailto:support@neuraldsp.com), have you tried using something like a Ebtech Hum X ground line voltage filter? There is going to be multiple variables for ground noise/static related issues. It sound like possible dirty power as well but just suggestions to try etc. A last effort to resolve could be backup and perform a factory reset. ---
**Author:** ![Ic3Ang3l](https://avatars.discourse-cdn.com/v4/letter/i/65b543/32.png) [@Ic3Ang3l](https://unity.neuraldsp.com/u/Ic3Ang3l)\ **Post date:** [July 17, 2023, 5:05pm UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/7 "2023-07-17T17:05:41Z")
Yeah, I am pretty sure that it is the preamp of the QC. Ground noise sound different. And no other device does such things. I tried several different wall plugs and even locations/rooms. I did several factory resets. Nothing changed. I heard from other people that they had the same problem but there was no real fix for it. So I am pretty sure its the preamp that is really noisy compared to other units on the market. ---
**Author:** ![MP\_Mod](https://avatars.discourse-cdn.com/v4/letter/m/ccd318/32.png) [@MP\_Mod](https://unity.neuraldsp.com/u/MP_Mod)\ **Post date:** [February 20, 2025, 6:33pm UTC](https://unity.neuraldsp.com/t/quad-cortex-static-noise-without-guitar-cable-plugged-in/11463/8 "2025-02-20T18:33:14Z")