need some ideas / direction trouble shooting this beast!
game is a system 9 space shuttle with garbled/distorted speech, this issue is related only to the portion of the speech sounds that originate from the speech board, the speech & audio that originates on the main board is clear and so are the other sounds generated on the main board
game arrived here DOA / not working with signs of previous sound problems (aka speaker wires cut at speakers)

what i have done ...
neutralized / repaired some minor acid damage to main board all located in the sound section area, replaced the 6808 with new (legs missing from original), and a new socket for it, new ribbon cable header pins, new ribbon cable (original cable had disintegrated),
new sockets for ROMs on the speech board, U4, U5 & U6
new cap at C-12 on speech board
all sound roms tested & have correct checksums
pulled both MC1458 op-amps, installed sockets and swapped them with no change, so either both of them are damaged or neither is damaged
Data lines are active & none are missing or stuck,
Address lines active - none missing or stuck
with audio probe i can only find distorted sounds on the speech board, checked input & output pins of the 55516 and sound is distorted at both locations
sound is also distorted at U13 PIA pin 19
both boards are properly grounded

since i can only find distorted / garbled speech no matter where i look i am pretty much out of ideas other than just replacing both MC1458 (and maybe thats the problem?)

any ideas would be greatly appreciated

well even tho i don't think they are at fault i ordered a pair of MC1458 op-amps from digikey - cheap too

keeping hope alive

as suspected replacing the pair of mc1458's accomplished nothing, originals were not at fault and i never thought they were but since i was placing an order what the hell
cost of experiment $.48 x 2
knowledge gained ... .0 aka zero/ nil / zed

how can i be the only person to encounter this issue

turned out to bad address line A-5 in the sound section causing the garbled speech, trace runs from the main board thru the ribbon cable to the speech pcb, originally there was acid damage under the 74ls08 which i previously replaced and is where this faulty trace is, i didn't notice the problem before since this line tested good with the multi-meter ... argh
i cut it, ran a jumper on the back and speech is much clearer
also replaced the main board sound rom socket while i was fixing shit on the main board
speech is not perfectly clear but its hella much better,
i honestly don't know what a space shuttle should sound like so it may be normal now