What revision ROMs do you have? The two different variants had rearranged setting IDs. We get these questions a lot for Flash due to this.

Not in the soundboard, the sounds aren't different - just the settings. Meaning: Setting 33 could be setting XX on the other ROM version and there is no issue, you simply just changed the wrong setting. (and changed something else, probably insignificant dealing with coin play or something)

They are on the MPU board. If they're original, there's green and yellow versions with matching-color stickers/labels on them. If not original, read the tags. If no tags, well, I guess we'll have to find the other value for the other set and you can give that a go!

Try adjusting setting 31 to 01.

Also, to change the old one back: Setting 33 on the alternate revision is "SUPER FLASH Restore".

00: Restores
01: Does Not Restore

(Whatever this means to you. The default is the 00 setting, also sounds like the best)

No problem! Enjoy! Buzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz... (I love it too!)

Sent you this when you asked in PM, but here it is for the public: http://mirror2.ipdb.org/files/871/Williams_1979_Flash_Manual_Amendment_WMA486_2_color_coded_ROMs_and_PROMS_undated.pdf

Thanks to everyone on this post! Ran into the same and this just fixed my issue. Stashing the manual amendment away or future reference.

For future readers Flash had two different rom versions - I guess because the production run was so long.

To work out which you've got open the coin door, switch to auto/up position and press advance.

P1 display now shows the rom version

0486 1 or 0486 2 is yellow roms, system 4
1486 1 is green roms, system 6

the game rom must match the flipper rom

Background sound is setting 33 with yellow roms, 31 with green roms. In both cases 0 = off (default) and 1 = on.
Other settings changed between rom versions but it's sound that seems to get noticed, particularly because it defaults to off.

It's odd to me that since background sound was the big new feature, first seen on Flash, that the default was off.

i had the same issue but did not get lucky. have 486-2 when I fired it up and thats it aside from the gi. if i power down and back up it seems to work but all memory gets erased. batteries are new. holder is new. i changed #31 to 01 but i think i have to power it down to save the settings? not 100% sure on that. seems to add credit and do whacky stuff with ball in play too i have an kohout mpu here but its outfitted for black knight. have a message into them about that. i havent dug into the boards but it looks like the 40 pin connectors have been replaced. two upper rollovers arent working and the drops are terrible. just cleaned the middle bank and it at least works now but its still sluggy. i have all new wpc flipper assys on hand for when I get to that point but first things first. also have some major cupping on the larger round inserts. I will need to replace those. fun fun!

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So I have the same problem but my setting is 33-1 and I still have no background sound and my pop bumpers don't add points , I have sounds from hitting targets just. No build up constant background sound even when I enable it

IMG_2520 (resized).JPG

It depends on which ROM version do you have. If "yellow labeled" (usually sys4) the background sound option is #33; if "green label" (sys6), the function is #31.

I have the yellow rom i enable 33- to 1 but I still don't get the background sound that builds up and my pop bumpers won't add points they did then they stoped

But mine says this

image (resized).jpg

Thank you for this.. I found another thread talking about turning on setting 33, nothing in the manual of course about setting 31 if you have a different rom. Why was this even an option back then?