i recently installed some reverse glow gauges into my 91 civ. whenever the gauges begin getting power, they whine... its like a highpitch skreetching noise, and it changes in volume depending on the color setting (green is quieter than blue) and the brightness (brighter the display, louder the noise).

i've got them wired directly into the fuse box, and the ground directly onto the frame. any ideas?

 

Try a different ground. And maybe try a different fuse for your power.