Gyruss Issue #3 (The Gyruss problem trilogy)

[Jack]

Hey guys,
Do any of you know which chip on the board deals with music? The sounds work fine, but the music is either possessed sounding (Making random noises) or not making any music at all. I hope I don't need a new PCB or chip, because we don't have extra money right now because of the purchase of a Dixie-Narco soda machine. I hope I just need to reseat it or something.
Thanks for time,
The Cosmic Arcade

UPDATE 4-12
I found a loose wire and I found it went to the right speaker pot. I connected it and now I have my right channel unlike before. I get music on the right (not the full melody just the right side of the stereophonic equation) speaker but none still on the left, unless it wants to.

[John's Arcade]

Hey guys,
Do any of you know which chip on the board deals with music? The sounds work fine, but the music is either possessed sounding (Making random noises) or not making any music at all. I hope I don't need a new PCB or chip, because we don't have extra money right now because of the purchase of a Dixie-Narco soda machine. I hope I just need to reseat it or something.
Thanks for time,
The Cosmic Arcade

Are you sure the pots by the coin door are ok? The ones on my Gyruss are pretty dirty and if it's in the wrong spot I get no sound.

[Jack]

I get sound, just no music or it is all messed up sounding. The pots don't even make that old radio sound when you adjust the volume.

[John's Arcade]

I get sound, just no music or it is all messed up sounding. The pots don't even make that old radio sound when you adjust the volume.

Sorry, bro. I don't have any advice for you. This is my first Gyruss and mine works.

[Jack]

That is fine. I tried your advice and it worked... for a little while. The music worked fine for a while, then it started up again. I am going to re-seat all the chips to see what happens (when I have the time). Thanks for your help, though.

[Jack]

New Info!
I saw a video of the Gyruss soundtrack. I only hear the Main BGM theme. No percussion. I am going to research what chip deals with percussion and fiddle with it. I am going to need to watch John's chip burning tutorial possibly, and then it just might work. I'll keep you posted, Forum and have a good night or day or whatever time it is.

[Jack]

I found this:
# Audio processor I/O map
# I/O ports are aliased every 32 ports, i.e.: the top two bits are
# ignored. 00==20==40 ... 10==30==50 ..
#
#Port   Chip   Loc     Description
#------ ------ ------- ---------------------------------------------------
00-02   8910   11D     AY-3-8910 PSG, IOB = output control 1
03                    
04-06   8910   12D     AY-3-8910 PSG, IOB = output control 2
05                    
08-0A   8910   10B     AY-3-8910 PSG, IOA = clock control ?
0B                    
0C-0E   8910   9B      AY-3-8910 PSG
0F                    
10-12   8910   8B      AY-3-8910 PSG
13                    
14-17   8910   11D     Interrupt "Drum" chip (any value, any addr)
18-1B   8910   11D     "Drum" data; (valid commands listed below).
1C-1F      
I am going to fiddle with it this weekend. Chip location 11D I think. I'll keep you posted.