Clipping LEDs add "Hash" noise? (Rat Clone)

[Toy Sun]

I'm having an issue with a Rat clone I built (don't even remember the PCB supplier, but I've done a few and only this one, which I added switchable LED clipping to has this)

Pedal has a lot of "hash" noise. Not hum, not buzz, but when it's on, and sitting idle, there will be an intermittent scratch/hashy sound. It seems to go away/reduce when the pedal has been on for a while, but that's likely totally my impression. I really sounds like a bad solder joint, electromechanical, but manipulating the device, wiggling things has no impact.

Then I saw this post:
https://www.diystompboxes.com/smfforum/index.php?topic=125362.msg1194106#msg1194106

Where Pinkjimiphoton said this:  i use them uv ones all the time they look cool, but seem to contribute to "hash" on the power rails

And it got me thinking: are my LEDs causing this? Different color better?  My LEDs are white (and they light up) and they sound good - in my testing on the BB, I liked white the best.

Any thoughts?

Thanks
John

[Govmnt_Lacky]

Seeing as the typical Red clipping LEDs have an Fv of 1.7 to 2V and the White LEDs are 3-5V... I would say it might be a factor.

[antonis]

Try to get LEDs out of circuit (lift their GND connection - or Vref, if connected so.. ) and see what happens..

[MikeA]

LEDs can generate current when exposed to light.  Is the circuit boxed up so the LEDs aren't in direct light?  If an audio probe doesn't isolate it to something in the signal path, I would look for external noise sources nearby: Cell phone in the pocket? Laptop? Digital pedal on the same power supply?

[Rob Strand]

For the purposes of debugging temporarily replace the LED with silicon diodes.  If you like replace each LED with two silicon diodes.

What I think you will find is the hash is there even with the silicon diodes.
ie. the problem is elsewhere and not caused by the LEDs.   

It's going to be something related the way you are switching
the diodes or the way the wiring is done to the switch.