Is there any way to get rid of this annoying sound? I've attached a link below to a video so you can see and hear what I'm talking about. My machine had a subtle hum to begin with but I just added the new Alltek lamp driver board and it became much louder and more noticeable.

I'd love to hear your opinions. I believe it's the transformer sound running through the speaker.

Video - https://vimeo.com/206793273

Updated Video! This is what it sounds like now after trying what Quench suggested. Much better but something is still humming. - https://vimeo.com/207215612

Thanks for the info! I'll try removing those two screws and pulling the sound board away from the metal frame at the screw points. I'll let you know if it does the trick!

Inkochnito Thanks for the info! I haven't tried that. I've attached a picture of a sound board below (not my sound board), would you mind showing me where the caps are? I tried searching around on Google but I couldn't find a video or anyone replacing caps on this specific sound board.

50sndboardkiss (resized).jpg

pinkid Sorry, that wasn't a picture of my soundboard. I was just using it as a example to find out what "caps" were until I realized "caps" meant capacitors. I'll try isolating the sound board first and then if that doesn't work, I'll look at replacing the caps. More importantly, what did you use to insulate the sound board? Did you use fiber washers on both sides of the sound board (front and back)?

Quench Would you mind sharing the size of the fiber washers you purchased? It will save me from having to take the backglass off and look before I go to Home Depot.

After doing what Quench suggested I do (https://pinside.com/pinball/forum/topic/kiss-pinball-79/page/3#post-3624637), the hum almost went completely away! Thank you so much!

Quench Would you recommend putting washers on any of the other boards? The hum went away immensely but i'm still hearing a faint hum. Not sure what it's from. Would you mind taking a look at my updated video? https://vimeo.com/207215612

The more noticeable hum seems to happen when the four KISS letters all light up at the same time on the back box.

I feel as if the hum is coming from whichever board is controlling the middle lights which I believe is the lamp driver board. Also, i think it's coming from whichever board controls the KISS sequential letters in the back box. I thought I heard somewhere that the KISS letters are on a separate board than the mpu. Maybe if I put washers on those two boards, the hum will be gone completely?