Multi colored LED

So I wrapped up this Töbe Screamer (Danae) featuring my cat Toby. I got these 3 mm color changing LEDs and it works great no issues.

Now any circuit I've tried since I get a high pitch whiney sound as it changes. Any idea why and/Or any fixes?

I'll try to get some audio of the noise when I get home from work.
 

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The LED changes colors with two pins, or there’s multiple pins, each being a separate anode/cathode (depending on the type)? The former has circuitry that is cycling the colors. That cycling can introduce noise into the ground or power line. I’d suggest avoiding them in audio circuits.
Its the 2 pin type. Im guessing I just got lucky with the first build not having any noise.
 
Great artwork.

Those LEDs are known to do that. There is a microcontroller or gate array inside that uses PWM to vary the brightness of three LEDs. You can try sticking a 100uF cap across the LED to absorb the current spikes. I put one of those fading rainbow LEDs on my headphones amp. It's pretty, but even with the 100uF cap I still hear a faint squeal. Lesson: avoid putting noise generators in pedals.
 
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