SuperHeterodyne Receiver weird sound

[Baran]

Hello guys,

I recently assembled the Superheterodyne receiver, but I'm having some issue.
The pedal works, btpass works, when engaged I can enjoy all the different effects the pedal provides but there is always a wissing sound in the background that screw everythings up.
It seems that when the tone knob of my guitar is at 0 the wissing sound is less but it is still here. I honestly don't know from where it comes from. If anyone has ideas please let me know.
Video for the sound: https://streamable.com/7wjz0n

Thanks!

 

[giovanni]

I would start By cleaning the board. It looks pretty dirty. Then I wonder where you got the ICs? One of them may be faulty or counterfeit. That level of noise is definitely not normal.

 

[Baran]

Thanks for that.

Cleaning the board with isopropyl alcohol right?

As for the ICs, I bought them to the local shop I don't think they are counterfeit (at least I hope so), do you know how to be sure? In the case they may be faulty, do you know how to verify so?

 

[giovanni]

Isopropyl yes. You can only verify by replacing them and checking. You do it one at a time.