OK.Typical issue on this board, this may have multiple causes.The fault is most likely located on the middle CPU board (but it can be also on top CPU board where program ROMs sit).
Here you go :
https://www.tindie.com/products/caiusarcade/054544-replacement-dacasic-not-included/
Choose the option if you want the AD1868R DAC included
Mitsubishi 'MN50005XTA' and 'M60002-0118P' reproduction
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Testing :
Capcom '86S105' reproduction
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'ALPHA-8921/PRO-CT0' reproduction
Original custom IC :
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Data East 'RCDM-I4/RCDM-I5' reproduction
Original custom IC :
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Update with new custom IC reproductions :
Taito 'PC050CM'
Original custom IC :
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SNK I/O
Original custom IC :
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