Yes the problem can come from the driver (Q10 or latches 74175), or the sound card. Unfortunately, on the SYS 80A, Gotllieb has not planned a test for sounds (what a shame!). I had done a few years ago, a special ROM (2716) for tests, that played all the sounds of a SYS 80A, but I do not remember where I put the binary file!
There is a tip you can try, to identify if the sound board is able to play the voices correctly : force the S16 signal to the ground.
The sound signals (S1..S16) works with negative logic : a "1" level is grounded, a "0" is at +5v (with pullup resistor).
So, the sound $01 has S1 grounded, and S2, S4, S8, S16 pull to +5v
To force the S16 signal to 1, it should be forced to ground. Easy to do on the sound board : connect a wire (using a grip - or even with a temporary welded strap) between the two resistors R30 / R24 as shown :
This will permanently drive the S16 to ground (set it to "1" logic level).
No risk to burn the Q10 (L9 output) as this one also drive a ground signal.
At the beginning of a game (add credits, and press the replay button), the DD will execute the following sequence:
- Play a sound $04 (S4 goes to ground)
- Eject the ball, and wait for the 3rd trough switch (SW51 - this check that the ball has been ejected)
- Play a series of sounds $0A (S8 and S2 goes to go ground)
- Play the voice $14 - "FIRE" - (S4 and S16/L9 goes to ground)
With S16 forced to ground, the message "FIRE" should be played twice (at start, and after ejecting the ball - and of course, another sound between them).
If you heard the "FIRE" voice, then this mean that the sound board works fine, and the problem is on the driver.
If not, then the culprit is the sound board.
In this case, it could be U24 (LM393), U16 (7404) or even the U15 (6532).
Another stupid idea to verify : be sure that you have an U.S. Devil's Dare Game ROM
Because there is an export model, and this one use the simple "6530" sound board. The rules ares the same, but the sound commands are dedicated to this board.. and have only 16 sounds - and as far as I remember - the S16 signal is never active in this version.