LED light makes high-pitched noise

[bobcunningham]

ok. first time poster, long time lurker;
i've successfully built a number of beginner-level pedals already and just recently began adding LED lights to my pedals.
THAT is when the trouble began. now whenever one of my LED-loaded pedals in ON there is a high-pitched whine ringing out through the amp. it should be noted that we're only talking about simple Bazz Fuss or similar circuits.
what i know for certain is that the LED is the source of the noise. they are Radio Shack LEDs. one lug of the 3pdt switch to one end of the LED, 4.7K resistor on the other end to 9 volt. middle lug of the 3pdt is grounded on the input jack.
what i'm saying is this: when i unsoldered the LED the high pitched whine went away and everything was fine. re-attach the LED and the whine returns.
this seems to me like a simple fix, but i don't know where to start. i would really appreciate any and all suggestions.

[PRR]

Battery? Or switcher wall-wart power?

[~arph]

Color changing LED?  they do that.

Also, try a capacitor over the led's two lugs

[bobcunningham]

filtered and regulated wall-wart adapter.

what value capacitor across the LED?

[~arph]

Doesn't really matter, not too small. say: .1 to 1uF
But is it a color changing LED or a normal one?

[bobcunningham]

plain LED light
1 pedal has a 5mm blue
the other has a 3mm green
same high-pitched whine coming through both.

[bobcunningham]

capacitor across the poles of the LEDs have no effect. any other ideas?
i've tried various resistor values as well as capacitor values and still have the annoying high-pitched sound coming through.

[deadastronaut]

is it wired the same as this....?

http://www.forrestwhitesides.com/files/up/img/tut/wiring/3pdt_wiring.jpg

there are various ways of wiring 3pdt's...

never heard of screaming leds though!....

another diagram..

http://img.photobucket.com/albums/v75/kev93_10/3pdt-wiring_png.png?t=1244105908

this second one i use always with no problems at all...

[bobcunningham]

i'm going to verify the switch wiring and try your suggestions today. i'll keep you posted.

[bobcunningham]

my switches are roughly wired like your first example. i've just tried the wiring method shown in your second example and i screwed up somewhere. still need to work this out.

[bobcunningham]

IT WORKS! IT WORKS! thanks Deadastronaut! i rewired the switch according to your second diagram and ALL is functioning and noise-free!!!!

today, with the help of others, i've succeeded in Tone Controls AND noise-free LEDs.

a million thanks. it was a good day.

[deadastronaut]

great...glad you got them going......yeah , thought it might be the switch wiring..

now play the buggers....